Recent Releases of Mesa 3

Mesa 3 - v3.2.0

Highlights

Mesa 3.2.0 is a feature-packed release, which stabilizes our discrete space, improves many of our visualisation capabilities, improves our tutorial organization, adds the experimental meta-agents, and includes other quality of life enhancements.

We also celebrate the publication of our peer-reviewed Mesa 3 paper in JOSS. See the updated Citing Mesa section on how to cite us.

Stabilization of Discrete Space

The experimental Cell Space system has been stabilized and is now available as mesa.discrete_space (#2610). This powerful spatial modeling framework enables cell-centric simulations with integrated PropertyLayers and improved agent movement capabilities. Key improvements include:

Support for dynamic modifications to discrete spaces during simulation (#2755)
Methods to add/remove cells and connections in real-time
Full integration with PropertyLayers (#2440) for representing environmental variables
Compatible with all examples and existing visualizations

The PropertyLayer itself has also been stabilized, allowing for efficient management of spatial environmental properties like terrain, resources, or any grid-based variables. Core examples including Schelling, Game of Life, Boltzmann Wealth, and Virus on Network have been updated to use the new discrete space system.

Enhanced Visualization Experience

The SolaraViz visualization system has received substantial upgrades:

Command Console (#2697): An interactive Python console embedded directly in the visualization, allowing real-time model inspection and manipulation
Asynchronous Updates (#2656): Visualization now runs in a separate thread, dramatically improving performance for complex models
Dark Mode (#2689): Support for Solara Dark theme, automatically matching system preferences
Improved Error Handling (#2747, #2753): Better visualization of errors with options to view detailed traceback information
Enhanced UI: Arrow key navigation (#2725), movable input field with auto-scroll (#2710), and other quality-of-life improvements
PropertyLayer visualisation in Altair (#2643): Support for visualising PropertyLayers using the Altair frontend in Solara.

Restructured and updated tutorial

Our introduction tutorial has been completely restructured (#2731). Instead of one huge notebook, the tutorial is now divided into smaller, focused modules that build progressively:

Creating Your First Model: Essential basics to get started
Adding Space: Learn how to use the new discrete space system
Collecting Data: Effectively gather model statistics
AgentSet: Master agent management techniques
Visualization: Series of modules covering basic to advanced visualization

Introducing Meta-Agents

Complex systems often have multiple levels of components. An organization is not one entity, but is made of departments, sub-departments, and people. A person is not a single entity, but it is made of micro biomes, organs and cells. A city is not a single entity, but it is made of districts, neighborhoods, buildings, and people. A forest comprises an ecosystem of trees, plants, animals, and microorganisms.

This reality is the motivation for meta-agents. It allows users to represent these multiple levels, where each level can have meta-agents with constituting agents. - Meta agents #2748

To demonstrate meta-agents capability there are two examples:

Dynamic meta-agent creation - Alliance formation, which shows emergent meta-agent formation through a game theoretic based alliance formation.
Deliberate meta-agent creation - Warehouse model, which provides a pseudo warehouse model to demonstrate meta-agent functionality.

Let us know what you think on our Matrix Channel

Other improvements

AgentSet's agg method now supports multiple aggregation functions in a single call (#2743)
Many documentation improvements have been made based on feedback by our JOSS reviewers

What's Changed

🎉 New features added

Stabilize experimental Cell Space as mesa.discrete_space by @quaquel in https://github.com/projectmesa/mesa/pull/2610
Feat: Added Command Console by @Sahil-Chhoker in https://github.com/projectmesa/mesa/pull/2697
Stabilize PropertyLayer by @EwoutH in https://github.com/projectmesa/mesa/pull/2440 ### 🛠 Enhancements made
Visualisation: Add dark mode by @sanika-n in https://github.com/projectmesa/mesa/pull/2689
Creating threads to update visualization asynchronously by @HMNS19 in https://github.com/projectmesa/mesa/pull/2656
Movable Input Field with auto-scroll by @Sahil-Chhoker in https://github.com/projectmesa/mesa/pull/2710
Feat: Added arrow key navigation by @Sahil-Chhoker in https://github.com/projectmesa/mesa/pull/2725
added property_layer with altair by @sanika-n in https://github.com/projectmesa/mesa/pull/2643
Debug option for errors in visualisation by @colinfrisch in https://github.com/projectmesa/mesa/pull/2747
Debug option for errors in visualisation front end by @colinfrisch in https://github.com/projectmesa/mesa/pull/2753
Add support for dynamic discrete spaces by @quaquel in https://github.com/projectmesa/mesa/pull/2755
Support multiple functions in AgentSet agg method by @EwoutH in https://github.com/projectmesa/mesa/pull/2743 ### 🔍 Examples updated
Move boltzmann to cell spaces by @quaquel in https://github.com/projectmesa/mesa/pull/2680
Move Game of life to cell space by @quaquel in https://github.com/projectmesa/mesa/pull/2681
Move Schelling to discrete space by @quaquel in https://github.com/projectmesa/mesa/pull/2684
Move virusonanetwork to discretespace by @quaquel in https://github.com/projectmesa/mesa/pull/2688
Update boid_flockers example include flight direction by @sanika-n in https://github.com/projectmesa/mesa/pull/2696 ### 📜 Documentation improvements
docs: Split off the overview page, extend with spaces/activation by @EwoutH in https://github.com/projectmesa/mesa/pull/2673
docs: Add Roles section to CONTRIBUTING.md by @EwoutH in https://github.com/projectmesa/mesa/pull/2694
[JOSS] Docs: Clarify difference between core and user examples by @EwoutH in https://github.com/projectmesa/mesa/pull/2706
[JOSS] docs: Improve batch_run documentation for parallel processing by @EwoutH in https://github.com/projectmesa/mesa/pull/2707
JOSS Tutorial Fixes by @tpike3 in https://github.com/projectmesa/mesa/pull/2708
Clean-up old images, compress wolf-sheep image, remove version switch artifact by @EwoutH in https://github.com/projectmesa/mesa/pull/2717
docs: Update citation to JOSS article by @EwoutH in https://github.com/projectmesa/mesa/pull/2740
update intro tutorial discrete space by @tpike3 in https://github.com/projectmesa/mesa/pull/2731
docs: fix broken links to Readthedocs in example descriptions by @reyan-singh in https://github.com/projectmesa/mesa/pull/2757 ### 🧪 Experimental features
Meta agents by @tpike3 in https://github.com/projectmesa/mesa/pull/2748 ### 🐛 Bugs fixed
Minor (bug) fixes to discrete_space by @quaquel in https://github.com/projectmesa/mesa/pull/2687
Fixed Marker in mpl by @sanika-n in https://github.com/projectmesa/mesa/pull/2670

New Contributors

@colinfrisch made their first contribution in https://github.com/projectmesa/mesa/pull/2747
@reyan-singh made their first contribution in https://github.com/projectmesa/mesa/pull/2757

Full Changelog: https://github.com/projectmesa/mesa/compare/v3.1.4...v3.2.0

Scientific Software - Peer-reviewed - Python
Published by EwoutH 8 months ago

Mesa 3 - v3.1.5

Highlights

Mesa 3.1.5 is a maintenance release focused on improving documentation and cleaning up our resources. This update includes no breaking changes and is compatible with previous 3.1.x releases.

The documentation improvements include enhanced explanations for batch run parallel processing, a significantly expanded overview section covering spaces, property layers and time advancement methods with practical code examples, and a clearer installation guide detailing what the optional [rec] dependencies provide. We've also improved our examples documentation to better distinguish between core and user-contributed examples, and added a new "Roles" section to the contributing guide that outlines the project's community structure and progression paths.

On the maintenance side, we've cleaned up unused images and compressed existing ones, reducing the repository size by over 2MB and distribution size from 3.2MB to 1.2MB.

We recommend all users update to this release for the improved documentation.

What's Changed

📜 Documentation improvements

docs: Split off the overview page, extend with spaces/activation by @EwoutH in https://github.com/projectmesa/mesa/pull/2673
docs: Add Roles section to CONTRIBUTING.md by @EwoutH in https://github.com/projectmesa/mesa/pull/2694
[JOSS] Docs: Clarify difference between core and user examples by @EwoutH in https://github.com/projectmesa/mesa/pull/2706
[JOSS] docs: Improve batch_run documentation for parallel processing by @EwoutH in https://github.com/projectmesa/mesa/pull/2707
Clean-up old images, compress wolf-sheep image, remove version switch artifact by @EwoutH in https://github.com/projectmesa/mesa/pull/2717

Full Changelog: https://github.com/projectmesa/mesa/compare/v3.1.4...v3.1.5

Scientific Software - Peer-reviewed - Python
Published by EwoutH 9 months ago

Mesa 3 - v3.1.4

Highlights

This release contains various improvements and bugfixes to the matplotlib-based visualization of spaces. Hexgrids are now fully supported, including property layers. In making this possible, various minor bugs were encountered and also fixed. In addition to the visualization improvements, there are various minor convenience improvements to the docs.

What's Changed

🛠 Enhancements made

Fixed hex-space draw function to avoid overlaps by @Sahil-Chhoker in https://github.com/projectmesa/mesa/pull/2609
Fix: Property layer visualization for HexGrid by @Sahil-Chhoker in https://github.com/projectmesa/mesa/pull/2646
Enhance DataCollector to validate model_reporters functions by @peter-kinger in https://github.com/projectmesa/mesa/pull/2605
Implemented post_process in Altair based components by @sanika-n in https://github.com/projectmesa/mesa/pull/2641 ### 🐛 Bugs fixed
bugfix for drawpropertylayer by @quaquel in https://github.com/projectmesa/mesa/pull/2639
Uses array for hex grid property layer fix by @Sahil-Chhoker in https://github.com/projectmesa/mesa/pull/2651
Update Binder environment to use latest Mesa version (#2652) by @aarav-shukla07 in https://github.com/projectmesa/mesa/pull/2655
Change Hexgrid.connectcells_2d to use x,y coordinates by @quaquel in https://github.com/projectmesa/mesa/pull/2632 ### 🔍 Examples updated
Added property layer viz to sugarscape by @sanika-n in https://github.com/projectmesa/mesa/pull/2653
added color-bar for spice by @sanika-n in https://github.com/projectmesa/mesa/pull/2622 ### 📜 Documentation improvements
remove any reference to using --pre by @quaquel in https://github.com/projectmesa/mesa/pull/2618
Updated Docs by @sanika-n in https://github.com/projectmesa/mesa/pull/2624
Fixed 404 error for Examples Tab in Introductory Tutorial (#2662) by @aarav-shukla07 in https://github.com/projectmesa/mesa/pull/2664
Documentation by @Spartan-71 in https://github.com/projectmesa/mesa/pull/2630
Adding a copy option at the top of the code written in the docs by @PrashantChoudhary13579 in https://github.com/projectmesa/mesa/pull/2628
Adding Mesa Extension page by @PrashantChoudhary13579 in https://github.com/projectmesa/mesa/pull/2627 ### 🔧 Maintenance
remove remnants of mesa cli by @quaquel in https://github.com/projectmesa/mesa/pull/2617
benchmarks.yml: Install SciPy and use uv for pip install by @EwoutH in https://github.com/projectmesa/mesa/pull/2633
[pre-commit.ci] pre-commit autoupdate by @pre-commit-ci in https://github.com/projectmesa/mesa/pull/2659

New Contributors

@PrashantChoudhary13579 made their first contribution in https://github.com/projectmesa/mesa/pull/2628
@aarav-shukla07 made their first contribution in https://github.com/projectmesa/mesa/pull/2655
@peter-kinger made their first contribution in https://github.com/projectmesa/mesa/pull/2605

Full Changelog: https://github.com/projectmesa/mesa/compare/v3.1.3...v3.1.4

Scientific Software - Peer-reviewed - Python
Published by quaquel 11 months ago

Mesa 3 - v3.1.3

Highlights

Mesa 3.1.3 introduces a major experimental reimplementation of Mesa's continuous space, providing an intuitive agent-centric API and significant performance improvements. The new implementation supports n-dimensional spaces and offers streamlined methods for agent movement and neighbor calculations.

New Continuous Space Features

Agent-centric movement API similar to cell spaces
Efficient neighbor calculations and position updates
Support for n-dimensional spaces
Improved memory management with dynamic array resizing

Here's a quick look at the new API:

```python

Create a 2D continuous space

space = ContinuousSpace( dimensions=[[0, 1], [0, 1]], torus=True, random=model.random )

Create and position an agent

agent = ContinuousSpaceAgent(space, model) agent.position = [0.5, 0.5]

Move agent using vector arithmetic

agent.position += [0.1, 0.1]

Get neighbors within radius

neighbors, distances = agent.getneighborsin_radius(radius=0.2)

Find k nearest neighbors

nearest, distances = agent.getnearestneighbors(k=5) ```

The new implementation particularly benefits models requiring frequent position updates and neighbor queries, such as flocking simulations or particle systems. See PR #2584 and the API documentation for more details. We would love to get feedback on the new Continuous Space in #2611.

Other improvements in this release include consistent visualization behavior across space types with the reimplementation of draw_voronoi #2608, and a new render interval slider for controlling visualization update frequency in SolaraViz, which helps improve performance when working with complex visualizations #2596. We've also fixed a bug affecting random number generation determinism when using Model(seed=something), ensuring both model.random and model.rng now behave consistently when seeded with the same initial value #2598.

What's Changed

🧪 Experimental features

Reimplementation of Continuous Space by @quaquel in https://github.com/projectmesa/mesa/pull/2584 ### 🛠 Enhancements made
reimplementation of draw_voroinoi by @quaquel in https://github.com/projectmesa/mesa/pull/2608
Add render interval slider to control visualization update frequency by @HMNS19 in https://github.com/projectmesa/mesa/pull/2596 ### 🐛 Bugs fixed
Bugfix for non deterministic rng behavior by @quaquel in https://github.com/projectmesa/mesa/pull/2598 ### 🔍 Examples updated
Clarify ContinuousSpace.get_neighbors behavior with multiple agents at same position by @quaquel in https://github.com/projectmesa/mesa/pull/2599

New Contributors

@HMNS19 made their first contribution in https://github.com/projectmesa/mesa/pull/2596

Full Changelog: https://github.com/projectmesa/mesa/compare/v3.1.2...v3.1.3

Scientific Software - Peer-reviewed - Python
Published by EwoutH 12 months ago

Mesa 3 - v3.1.2

Highlights

Mesa v3.1.2 is a patch release containing updates to our wolf-sheep, shelling and prisoner's dilemma example models and improving documentation in the tutorials and visualisation docstring. No functional changes to the core library were made.

What's Changed

🔍 Examples updated

examples/wolf_sheep: Don't allow dumb moves by @EwoutH in https://github.com/projectmesa/mesa/pull/2503
Added homophily ratio in basic schelling example by @vbv-shm in https://github.com/projectmesa/mesa/pull/2520
examples: Update pd_grid analysis.ipynb to use new spaces by @quaquel in https://github.com/projectmesa/mesa/pull/2553 ### 📜 Documentation improvements
Corrected a few errors in Intro tutorial by @sanika-n in https://github.com/projectmesa/mesa/pull/2583
Small draw_space docstring fix by @quaquel in https://github.com/projectmesa/mesa/pull/2554
fix: model name in visualization tutorial by @Sahil-Chhoker in https://github.com/projectmesa/mesa/pull/2591

New Contributors

@vbv-shm made their first contribution in https://github.com/projectmesa/mesa/pull/2520
@sanika-n made their first contribution in https://github.com/projectmesa/mesa/pull/2583

Full Changelog: https://github.com/projectmesa/mesa/compare/v3.1.1...v3.1.2

Scientific Software - Peer-reviewed - Python
Published by EwoutH 12 months ago

Mesa 3 - v3.1.1

Highlights

Mesa 3.1.1 is a maintenance release that includes visualization improvements and documentation updates. The key enhancement is the addition of an interactive play interval control to the visualization interface, allowing users to dynamically adjust simulation speed between 1ms and 500ms through a slider in the Controls panel.

Several example models were updated to use Mesa 3.1's recommended practices, particularly the create_agents() method for more efficient agent creation and NumPy's rng.integers() for random number generation. The Sugarscape example was modernized to use PropertyLayers.

Bug fixes include improvements to PropertyLayer visualization and a correction to the Schelling model's neighbor similarity calculation. The tutorials were also updated to reflect current best practices in Mesa 3.1.

What's Changed

🎉 New features added

Add Interactive Play Interval Control to Mesa Visualization by @AdamZh0u in https://github.com/projectmesa/mesa/pull/2540 ### 🐛 Bugs fixed
bug fixes for drawpropertylayers by @quaquel in https://github.com/projectmesa/mesa/pull/2548 ### 🔍 Examples updated
Wolf-sheep to use create_agent by @quaquel in https://github.com/projectmesa/mesa/pull/2543
Shift sugarscape example to using create_agent by @quaquel in https://github.com/projectmesa/mesa/pull/2544
Fix: Schelling Model Neighbor Similarity Calculation by @Sahil-Chhoker in https://github.com/projectmesa/mesa/pull/2518
Change pdgrid example to use createagents by @quaquel in https://github.com/projectmesa/mesa/pull/2545
Switch sugarscape to using property layers by @quaquel in https://github.com/projectmesa/mesa/pull/2546 ### 📜 Documentation improvements
Updated docs and check_model param by @nissu99 in https://github.com/projectmesa/mesa/pull/2510
Update tutorials to use create_agents and rng.integers by @DarshPareek in https://github.com/projectmesa/mesa/pull/2541

New Contributors

@nissu99 made their first contribution in https://github.com/projectmesa/mesa/pull/2510
@DarshPareek made their first contribution in https://github.com/projectmesa/mesa/pull/2541

Full Changelog: https://github.com/projectmesa/mesa/compare/v3.1.0...3.1.1

Scientific Software - Peer-reviewed - Python
Published by EwoutH about 1 year ago

Mesa 3 - v3.1.0

Highlights

With Mesa 3.1.0 we're back on our regular release schedule after the big Mesa 3.0 release, with some exciting new features.

This release adds experimental support for Observables and Computed, enabling a more reactive and responsive programming model for agent-based simulations. The new Observable and Computable classes allow developers to declaratively define attributes that automatically emit signals when their values change, and compute derived values that update dynamically. This lays the groundwork for more advanced event handling and data visualization features in future releases (#2291).

The experimental cell space module has been updated with full support for n-dimensional property layers. These allow agents to easily interact with and modify spatial properties of the environment, such as terrain, resources, or environmental conditions. The new implementation provides a more intuitive attribute-based API and ensures tight integration with the cell space architecture (#2512).

Mesa now includes built-in support for logging using the standard Python logging module. This provides developers with a flexible and powerful way to add structured diagnostic and debug output to their simulations, without the need for custom logging solutions. The logging system is integrated throughout the library, including the new SolaraViz visualization system (#2506).

Creating multiple agents with varying initialization parameters is now significantly easier with the new Agent.create_agents class method. This factory function supports both uniform and per-agent parameters, simplifying the code required to set up a simulation with a large number of heterogeneous agents (#2351).

In addition to the major new features, this release includes a number of smaller enhancements and bug fixes that improve the overall developer experience. These include removing deprecated functionality, cleaning up examples, and addressing various edge cases reported by the community. Mesa 3.1 requires Python 3.11 or higher.

What's Changed

🧪 Experimental features

Add support for Observables to MESA by @quaquel in https://github.com/projectmesa/mesa/pull/2291
Add full support for property layers to cell spaces by @quaquel in https://github.com/projectmesa/mesa/pull/2512 ### 🎉 New features added
Add logging to MESA by @quaquel in https://github.com/projectmesa/mesa/pull/2506
Add create_agents factory method to Agent by @quaquel in https://github.com/projectmesa/mesa/pull/2351 ### 🔍 Examples updated
Add seed control to all examples by @quaquel in https://github.com/projectmesa/mesa/pull/2496 ### 📜 Documentation improvements
doc fix for pip install error on mac by @quaquel in https://github.com/projectmesa/mesa/pull/2508
Refactored docs for Introductory Tutorial by @Spartan-71 in https://github.com/projectmesa/mesa/pull/2511
Add module-level docstring to experimental features by @EwoutH in https://github.com/projectmesa/mesa/pull/2532 ### 🔧 Maintenance
Remove deprecated time module by @EwoutH in https://github.com/projectmesa/mesa/pull/2476
Drop support for Python 3.10, require Python >= 3.11 by @EwoutH in https://github.com/projectmesa/mesa/pull/2474
Remove deprecated functionality by @EwoutH in https://github.com/projectmesa/mesa/pull/2483
Remove visualization modules from mesa.experimental by @quaquel in https://github.com/projectmesa/mesa/pull/2495
Cleanup two occurrences of removed scheduler by @EwoutH in https://github.com/projectmesa/mesa/pull/2499
move setupagentregistration into `Model.init_` by @quaquel in https://github.com/projectmesa/mesa/pull/2501
remove devs related examples from devs/examples by @quaquel in https://github.com/projectmesa/mesa/pull/2507
added empty iterable checks and updated tests by @Sahil-Chhoker in https://github.com/projectmesa/mesa/pull/2523
Fix: running Mesa in Docker with Schelling model by @AdamZh0u in https://github.com/projectmesa/mesa/pull/2524

New Contributors

@Spartan-71 made their first contribution in https://github.com/projectmesa/mesa/pull/2511
@Sahil-Chhoker made their first contribution in https://github.com/projectmesa/mesa/pull/2523
@AdamZh0u made their first contribution in https://github.com/projectmesa/mesa/pull/2524

Full Changelog: https://github.com/projectmesa/mesa/compare/v3.0.3...v3.1.0

Scientific Software - Peer-reviewed - Python
Published by EwoutH about 1 year ago

Mesa 3 - v3.0.3

Highlights

A small bugfix release that fixes two bugs.

What's Changed

🧪 Experimental features

cell_space: Allow CellCollection to be empty by @EwoutH in https://github.com/projectmesa/mesa/pull/2502 ### 🐛 Bugs fixed
Only set model_parameters once by @Corvince in https://github.com/projectmesa/mesa/pull/2505

Full Changelog: https://github.com/projectmesa/mesa/compare/v3.0.2...v3.0.3

Scientific Software - Peer-reviewed - Python
Published by EwoutH about 1 year ago

Mesa 3 -

Highlighst

Mesa 3.0.2 is a small follow-up patch release to Mesa 3.0, in which we fixed a lot of small bugs in the example models their visualisation, and improved their testing.

What's Changed

🐛 Bugs fixed

allow components as a positional argument again by @Corvince in https://github.com/projectmesa/mesa/pull/2488 ### 🔍 Examples updated
examples: Add required components keyword by @EwoutH in https://github.com/projectmesa/mesa/pull/2485
examples: Fix boid_flockers viz by @EwoutH in https://github.com/projectmesa/mesa/pull/2492
examples: Fix schelling viz by @EwoutH in https://github.com/projectmesa/mesa/pull/2490
example: Add input sliders to Sugerscape viz by @EwoutH in https://github.com/projectmesa/mesa/pull/2487
examples/gol: Add initial fraction alive, add sliders to viz by @EwoutH in https://github.com/projectmesa/mesa/pull/2489 ### 🔧 Maintenance
test app init of examples by @Corvince in https://github.com/projectmesa/mesa/pull/2491

Full Changelog: https://github.com/projectmesa/mesa/compare/v3.0.1...v3.0.2

Scientific Software - Peer-reviewed - Python
Published by EwoutH about 1 year ago

Mesa 3 - v3.0.1

Highlights

After our huge 3.0.0 release, Mesa 3.0.1 follows up with two improvements to experimental features, examples and docs.

What's Changed

🧪 Experimental features

Bugfixes to DEVS by @quaquel in https://github.com/projectmesa/mesa/pull/2478
Support simulators in SolaraViz by @quaquel in https://github.com/projectmesa/mesa/pull/2470 ### 🛠 Enhancements made
issue a user warning if random is None by @quaquel in https://github.com/projectmesa/mesa/pull/2479 ### 🔍 Examples updated
Integrate benchmarks and example models by @EwoutH in https://github.com/projectmesa/mesa/pull/2473 ### 📜 Documentation improvements
docs/tutorial: Replace scheduler in MoneyModel by @EwoutH in https://github.com/projectmesa/mesa/pull/2475
docs: update migration_guide.md by @eltociear in https://github.com/projectmesa/mesa/pull/2480
Update some DeprecationWarnings to note they are removed in Mesa 3.1 by @EwoutH in https://github.com/projectmesa/mesa/pull/2481

New Contributors

@eltociear made their first contribution in https://github.com/projectmesa/mesa/pull/2480

Full Changelog: https://github.com/projectmesa/mesa/compare/v3.0.0...v3.0.1

Scientific Software - Peer-reviewed - Python
Published by EwoutH about 1 year ago

Mesa 3 - v3.0.0

Highlights

After our most extensive pre-release program ever, we’re proud to release Mesa 3.0 as stable. Mesa 3.0 brings major improvements to agent-based modeling, making it more intuitive and powerful while reducing complexity. This release modernizes core functionalities and introduces new capabilities for both beginners and advanced users.

Streamlined agent management

The centerpiece of Mesa 3.0 is its new agent management system. Agents are now automatically tracked and assigned unique IDs, eliminating common boilerplate code. The new AgentSet functionality provides an elegant and flexible way to work with agents, for example:

```python

Find agents meeting specific criteria

wealthy_agents = model.agents.select(lambda a: a.wealth > 1000)

Group and analyze agents

grouped = model.agents.groupby("state") statestats = grouped.agg({ "count": len, "avgage": ("age", np.mean), "total_wealth": ("wealth", sum) })

Activate agents in different patterns

model.agents.shuffle_do("step") # Random activation model.agents.select(lambda a: a.energy > 0).do("move") # Conditional activation ```

The AgentSet provides powerful methods for filtering, grouping, and analyzing agents, making it easier to express complex model logic. Each model automatically maintains an AgentSet containing all agents (model.agents) and separate AgentSets for each agent type (model.agents_by_type). See the full AgentSet docs here.

Modern Visualization with SolaraViz

Mesa 3.0's new experimental visualization system, SolaraViz, provides a modern, interactive interface for model exploration:

```python from mesa.visualization import SolaraViz, makespacecomponent, makeplotcomponent

visualization = SolaraViz( model, [ makespacecomponent(agentportrayal), makeplotcomponent(["population", "averagewealth"]), lambda m: f"Step {m.steps}: {len(m.agents)} agents" # Custom text component ], modelparams=parametercontrols ) ```

Key visualization features: - Interactive browser-based interface with real-time updates - Support for both grid-based and network models - Visualization of PropertyLayers and hexagonal grids - Custom components using Matplotlib or text - Improved performance and responsiveness

Check out the Visualization Tutorial to get started.

Note: SolaraViz is in active development. We might make API breaking changes between Mesa 3.0 and 3.1.

Enhanced data collection

The DataCollector now supports collecting different metrics for different agent types, using agenttype_reporters:

python self.datacollector = DataCollector( model_reporters={"total_wealth": lambda m: m.agents.agg("wealth", sum)}, agent_reporters={"age": "age", "wealth": "wealth"}, agenttype_reporters={ Predator: {"kills": "kills_count"}, Prey: {"distance_fled": "total_flight_distance"} } )

Experimental features

Mesa 3.0 introduces several experimental features for advanced modeling: - Cell Space with integrated PropertyLayers and improved agent movement capabilities - Voronoi grid implementation - Event-scheduling simulation capabilities

These experimental features are in active development and might break API between releases.

Breaking changes

See our Mesa 3.0 migration guide for a full overview.

If you want to move existing models from Mesa 2.x to 3.0, there are a few things you have to change.

Models must explicitly initialize the Mesa base class: python class MyModel(mesa.Model): def __init__(self, n_agents, seed=None): super().__init__(seed=seed) # Required in Mesa 3.0
Agents are created without manual ID assignment: ```python

Old

agent = MyAgent(unique_id=1, model=self)

New

agent = MyAgent(model=self) ```
Scheduler replacement with AgentSet operations: ```python

Old (RandomActivation)

self.schedule = RandomActivation(self) self.schedule.step()

New

self.agents.shuffle_do("step")

Old (SimultaneousActivation)

self.schedule = SimultaneousActivation(self) self.schedule.step()

New

self.agents.do("step") self.agents.do("advance") ```

Furthermore: - Steps counter automatically increments - mesa.flat namespace removed - Python 3.10+ required - Reserved model variables (agents, steps, etc.) protected - Simplified DataCollector initialization - Old visualization system replaced by SolaraViz

Getting Started

Install Mesa 3.0: bash pip install --upgrade mesa

If building a new model, we recommend checking out the updated Mesa Overview and Introductory Tutorial.

For updating existing models, we recommend upgrading in steps: 1. Update to latest Mesa 2.x 2. Address deprecation warnings 3. Upgrade to Mesa 3.0 4. Replace schedulers with AgentSet functionality

A detailed migration guide is available to help moving to Mesa 3.0. For questions or support, join our GitHub Discussions or Matrix Chat.

We would love to hear what you think about Mesa 3.0! Say hello here and leave any feedback on 3.0 here.

What's Changed

⚠️ Breaking changes

Remove mesa.flat namespace by @rht in https://github.com/projectmesa/mesa/pull/2091
breaking: Remove visualization_old (mesa-viz-tornado) by @rht in https://github.com/projectmesa/mesa/pull/2133
viz: Combine code for rendering in browser and Jupyter by @rht in https://github.com/projectmesa/mesa/pull/2180
breaking: Add dependencies argument to custom space_drawer by @rht in https://github.com/projectmesa/mesa/pull/2209
Require Mesa models to be initialized with super().__init__() by @EwoutH in https://github.com/projectmesa/mesa/pull/2218
Allow AgentSet.do() to take Callable function by @quaquel in https://github.com/projectmesa/mesa/pull/2219
Change warning when setting model.agents to error by @EwoutH in https://github.com/projectmesa/mesa/pull/2225
model: Automatically increase steps counter by @EwoutH in https://github.com/projectmesa/mesa/pull/2223
move solara_viz back to experimental by @Corvince in https://github.com/projectmesa/mesa/pull/2278
track unique_id automatically by @quaquel in https://github.com/projectmesa/mesa/pull/2260
update Agent.init to remove deprecation warning by @quaquel in https://github.com/projectmesa/mesa/pull/2328
replace model with random in AgentSet init by @quaquel in https://github.com/projectmesa/mesa/pull/2350
remove cookiecutter by @quaquel in https://github.com/projectmesa/mesa/pull/2421
Viz: Refactor Matplotlib plotting by @quaquel in https://github.com/projectmesa/mesa/pull/2430
api reorganization by @quaquel in https://github.com/projectmesa/mesa/pull/2447
Deprecate initialize_data_collector by @EwoutH in https://github.com/projectmesa/mesa/pull/2327 ### 🧪 Experimental features
devs/eventlist: Add repr method to print EventList pretty by @EwoutH in https://github.com/projectmesa/mesa/pull/2195
Voronoi Tessellation based Discrete Space by @vitorfrois in https://github.com/projectmesa/mesa/pull/2084
Make cell connections public and named by @Corvince in https://github.com/projectmesa/mesa/pull/2296
Update to CellCollection.select by @quaquel in https://github.com/projectmesa/mesa/pull/2307
Have a dedicated neighborhood property and a get_neighborhood method on Cell by @quaquel in https://github.com/projectmesa/mesa/pull/2309
Encapsulate cell movement in properties by @quaquel in https://github.com/projectmesa/mesa/pull/2333
experimental: Integrate PropertyLayers into cell space by @EwoutH in https://github.com/projectmesa/mesa/pull/2319
Generalize CellAgent by @Corvince in https://github.com/projectmesa/mesa/pull/2292
cell space: Add convenience properties for grid width and height by @quaquel in https://github.com/projectmesa/mesa/pull/2348
Bugfix for deepcopy / pickling discrete spaces by @quaquel in https://github.com/projectmesa/mesa/pull/2378
Add support for drawing discrete grids by @quaquel in https://github.com/projectmesa/mesa/pull/2386
Altair spaces by @quaquel in https://github.com/projectmesa/mesa/pull/2397
Mark SolaraViz as experimental for Mesa 3.0 by @EwoutH in https://github.com/projectmesa/mesa/pull/2459 ### 🎉 New features added
Set JupyterViz as stable by @rht in https://github.com/projectmesa/mesa/pull/2090
Add AgentSet.groupby by @quaquel in https://github.com/projectmesa/mesa/pull/2220
AgentSet: Add set method by @EwoutH in https://github.com/projectmesa/mesa/pull/2254
AgentSet: Add agg method by @EwoutH in https://github.com/projectmesa/mesa/pull/2266
Implement new SolaraViz API by @Corvince in https://github.com/projectmesa/mesa/pull/2263
GroupBy: Add count and agg methods by @EwoutH in https://github.com/projectmesa/mesa/pull/2290
datacollector: Allow collecting data from Agent (sub)classes by @EwoutH in https://github.com/projectmesa/mesa/pull/2300
Add optimized shuffle_do() method to AgentSet by @EwoutH in https://github.com/projectmesa/mesa/pull/2283
Visualize PropertyLayers by @EwoutH in https://github.com/projectmesa/mesa/pull/2336
Move core example models back (v2) by @EwoutH in https://github.com/projectmesa/mesa/pull/2358
Add Model.rng for SPEC-7 compliant numpy random number generation by @quaquel in https://github.com/projectmesa/mesa/pull/2352
removeallagents method added to model by @quaquel in https://github.com/projectmesa/mesa/pull/2394
Pass through model.rgn in agent analogous to model.random by @quaquel in https://github.com/projectmesa/mesa/pull/2400
add agents property to all spaces by @quaquel in https://github.com/projectmesa/mesa/pull/2418 ### 🛠 Enhancements made
Rename JupyterViz to SolaraViz by @rht in https://github.com/projectmesa/mesa/pull/2187
refactor: Rename jupyterviz namespace to solaraviz by @rht in https://github.com/projectmesa/mesa/pull/2188
Visualisation: Allow specifying Agent shapes in agent_portrayal by @rmhopkins4 in https://github.com/projectmesa/mesa/pull/2214
Split AgentSet into map and do to seperate return types by @quaquel in https://github.com/projectmesa/mesa/pull/2237
Performance enhancements for Model.agents by @quaquel in https://github.com/projectmesa/mesa/pull/2251
AgentSet: Allow selecting a fraction of agents in the AgentSet by @EwoutH in https://github.com/projectmesa/mesa/pull/2253
Model: Replace get_agents_of_type method with agents_by_type property by @EwoutH in https://github.com/projectmesa/mesa/pull/2267
add default SolaraViz by @Corvince in https://github.com/projectmesa/mesa/pull/2280
Simplify ModelController by @Corvince in https://github.com/projectmesa/mesa/pull/2282
Add default values and missing value handling to agentset.get by @quaquel in https://github.com/projectmesa/mesa/pull/2279
SolaraViz Updates by @Corvince in https://github.com/projectmesa/mesa/pull/2299
Solara viz: use_task for non-threaded continuous play by @Corvince in https://github.com/projectmesa/mesa/pull/2304
Reduce core dependencies, split in optional dependencies by @EwoutH in https://github.com/projectmesa/mesa/pull/2265
use GridDraggable instead of Column in SolaraViz by @wang-boyu in https://github.com/projectmesa/mesa/pull/2344
update legend, xlabel & format of matplotlib plots by @wang-boyu in https://github.com/projectmesa/mesa/pull/2346
init.py: Import mesa.experimental by @EwoutH in https://github.com/projectmesa/mesa/pull/2374
Importable examples by @Corvince in https://github.com/projectmesa/mesa/pull/2381
update_tutorial environment by @tpike3 in https://github.com/projectmesa/mesa/pull/2411
expand ax.scatter kwargs that can be used by @quaquel in https://github.com/projectmesa/mesa/pull/2445 ### 🐛 Bugs fixed
datacollector: store separate snapshots of model data per step by @EwoutH in https://github.com/projectmesa/mesa/pull/2129
Jupyter_viz: Allow measures to be None by @EwoutH in https://github.com/projectmesa/mesa/pull/2163
Jupyter Viz: Don't avoid interactive backend by @EwoutH in https://github.com/projectmesa/mesa/pull/2165
fix: Render agent marker radius correctly by @rht in https://github.com/projectmesa/mesa/pull/2181
fix: Use model.schedule.steps -> mode.steps for batchrun by @rht in https://github.com/projectmesa/mesa/pull/2183
SolaraViz: Reset components when params are changed by @rht in https://github.com/projectmesa/mesa/pull/2240
Fix deterministic behavior in move_agent_to_one_of with selection="closest" by @OrenBochman in https://github.com/projectmesa/mesa/pull/2118
viz: stop running and disable buttons when model.running is False by @wang-boyu in https://github.com/projectmesa/mesa/pull/2332
experimental init: Fix Solara import by making it lazy by @EwoutH in https://github.com/projectmesa/mesa/pull/2357
fix: pass model.random to schedulers by @quaquel in https://github.com/projectmesa/mesa/pull/2359
fix: register agent after creating unique_id and pos attributes by @wang-boyu in https://github.com/projectmesa/mesa/pull/2368
solara: viz tutorial: fix histogram code by @Corvince in https://github.com/projectmesa/mesa/pull/2379
Fix for mistaken removal of drawgrid by @quaquel in https://github.com/projectmesa/mesa/pull/2398
fixes weakref bug in shuffe_do by @quaquel in https://github.com/projectmesa/mesa/pull/2399
Fix #2452 - handle solara viz model params better by @Corvince in https://github.com/projectmesa/mesa/pull/2454
Update MoneyModel.py by @quaquel in https://github.com/projectmesa/mesa/pull/2458
Bugfix for Solara deepcopy bug by @quaquel in https://github.com/projectmesa/mesa/pull/2460
solaraviz kwargs related bugfix by @quaquel in https://github.com/projectmesa/mesa/pull/2463 ### 🔍 Examples updated
Cleanup and restructure basic example models by @EwoutH in https://github.com/projectmesa/mesa/pull/2365
Ruff basic examples by @EwoutH in https://github.com/projectmesa/mesa/pull/2370
refactor: Simplify Schelling code by @rht in https://github.com/projectmesa/mesa/pull/2353
Move examples into mesa by @Corvince in https://github.com/projectmesa/mesa/pull/2387
Explicitly test basic examples by @quaquel in https://github.com/projectmesa/mesa/pull/2390
Make example import absolute by @quaquel in https://github.com/projectmesa/mesa/pull/2402
Cleanup and restructure EpsteinCivilViolence and PdGrid examples by @EwoutH in https://github.com/projectmesa/mesa/pull/2408
Reorganize advanced examples: wolfsheep and sugarscapeg1mt by @quaquel in https://github.com/projectmesa/mesa/pull/2410
reactivate ruff for advanced examples and include them in tests by @quaquel in https://github.com/projectmesa/mesa/pull/2414
Updates to Epstein example by @quaquel in https://github.com/projectmesa/mesa/pull/2429
Update examples to use updated space drawing by @quaquel in https://github.com/projectmesa/mesa/pull/2442 ### 📜 Documentation improvements
Fix image on landing page of docs. by @jackiekazil in https://github.com/projectmesa/mesa/pull/2146
Replace links in docs - google group to matrix. by @jackiekazil in https://github.com/projectmesa/mesa/pull/2148
Add experimental features to documentation as per #2122 by @stephenfmann in https://github.com/projectmesa/mesa/pull/2154
Update visualisation docs by @EwoutH in https://github.com/projectmesa/mesa/pull/2162
Add original conference paper link to docs by @ENUMERA8OR in https://github.com/projectmesa/mesa/pull/2160
docs/conf.py: Use modern intersphinx_mapping format by @EwoutH in https://github.com/projectmesa/mesa/pull/2206
docs: Update Readme and tutorials to mention Mesa 3.0 pre-releases by @EwoutH in https://github.com/projectmesa/mesa/pull/2203
Contribution: Add "I have no idea where to start" section by @EwoutH in https://github.com/projectmesa/mesa/pull/2258
Write initial Mesa Migration guide by @EwoutH in https://github.com/projectmesa/mesa/pull/2257
docs: Fix Visualization Tutorial (main branch) by @EwoutH in https://github.com/projectmesa/mesa/pull/2271
Docs: Fix broken relative links by removing .html suffix by @EwoutH in https://github.com/projectmesa/mesa/pull/2274
Readthedocs: Don't let notebook failures pass silently by @EwoutH in https://github.com/projectmesa/mesa/pull/2276
Update viz tutorial to the new API by @Corvince in https://github.com/projectmesa/mesa/pull/2289
Enforce google docstrings by @quaquel in https://github.com/projectmesa/mesa/pull/2294
Api docs by @quaquel in https://github.com/projectmesa/mesa/pull/2298
update migration guide to describe solaraviz updates by @Corvince in https://github.com/projectmesa/mesa/pull/2297
Migration Guide: Add Model initialization requirement and automatic Agent.unique_id assignment by @EwoutH in https://github.com/projectmesa/mesa/pull/2302
Deprecate Time module and all its Schedulers by @EwoutH in https://github.com/projectmesa/mesa/pull/2306
introtutorial: Don't initialize agents with an uniqueid by @EwoutH in https://github.com/projectmesa/mesa/pull/2315
Migration guide: Intro, upgrade strategy, model.agents, headers by @EwoutH in https://github.com/projectmesa/mesa/pull/2314
docs: Update overview for Mesa 3.0 by @EwoutH in https://github.com/projectmesa/mesa/pull/2317
Readthedocs: Add version switch and update URL by @EwoutH in https://github.com/projectmesa/mesa/pull/2324
Update migration_guide.md by @quaquel in https://github.com/projectmesa/mesa/pull/2347
Include examples in readthedocs (port) by @EwoutH in https://github.com/projectmesa/mesa/pull/2392
Update into_tutorial by @tpike3 in https://github.com/projectmesa/mesa/pull/2372
Update Schelling Readme.md by @quaquel in https://github.com/projectmesa/mesa/pull/2406
Update Conway example by @quaquel in https://github.com/projectmesa/mesa/pull/2403
Boltzman readme by @quaquel in https://github.com/projectmesa/mesa/pull/2405
Update Readme.md of Boid flockers by @quaquel in https://github.com/projectmesa/mesa/pull/2404
add advanced examples to rtd by @quaquel in https://github.com/projectmesa/mesa/pull/2413
Tutorial Improvements by @tpike3 in https://github.com/projectmesa/mesa/pull/2415
space: Add note that Grids are maintenance only by @EwoutH in https://github.com/projectmesa/mesa/pull/2420
Migration guide: Update automatic unique_id assignment examples by @EwoutH in https://github.com/projectmesa/mesa/pull/2419
Update docstring of SimEvent by @quaquel in https://github.com/projectmesa/mesa/pull/2417
best-practices: Update Model Layout section by @EwoutH in https://github.com/projectmesa/mesa/pull/2424
docs: Clean-up index.md by @EwoutH in https://github.com/projectmesa/mesa/pull/2422
Update wolf-sheep png and fix typo in file name by @quaquel in https://github.com/projectmesa/mesa/pull/2444
Include main examples readme in docs by @quaquel in https://github.com/projectmesa/mesa/pull/2448
remove how-to guide and update docs in places by @quaquel in https://github.com/projectmesa/mesa/pull/2449
Docs reorganization by @quaquel in https://github.com/projectmesa/mesa/pull/2450 ### 🔧 Maintenance
CI: Add weekly scheduled run to all CI workflows by @EwoutH in https://github.com/projectmesa/mesa/pull/2130
Drop support for Python 3.9, require Python >= 3.10 by @EwoutH in https://github.com/projectmesa/mesa/pull/2132
Add script to list unlabeled PR's since latest release by @rht in https://github.com/projectmesa/mesa/pull/2047
CI: Let pytest treat warnings as errors for examples by @EwoutH in https://github.com/projectmesa/mesa/pull/2204
CI: Add test job for Python 3.13 by @EwoutH in https://github.com/projectmesa/mesa/pull/2173
Add pull request templates by @EwoutH in https://github.com/projectmesa/mesa/pull/2217
benchmarks: Add BoltzmannWealth model by @EwoutH in https://github.com/projectmesa/mesa/pull/2252
CI: Add optional dependency for examples by @EwoutH in https://github.com/projectmesa/mesa/pull/2261
Resolve multiprocessing warning, state Python 3.13 support by @rht in https://github.com/projectmesa/mesa/pull/2246
make typing behavior of AgentSet.get explicit by @quaquel in https://github.com/projectmesa/mesa/pull/2293
model: Move random seed and random to init by @rht in https://github.com/projectmesa/mesa/pull/1940
Remove schedulers from benchmark models. by @quaquel in https://github.com/projectmesa/mesa/pull/2308
tests: Resolve warnings by removing scheduler and updating arguments by @EwoutH in https://github.com/projectmesa/mesa/pull/2329
add super call to Model and remove self.schedule by @quaquel in https://github.com/projectmesa/mesa/pull/2334
Code coverage: ignore experimental and visualization by @Corvince in https://github.com/projectmesa/mesa/pull/2361
add codecov token, fixes #2363 by @Corvince in https://github.com/projectmesa/mesa/pull/2366
add test_time back by @quaquel in https://github.com/projectmesa/mesa/pull/2367
Release notes: Add example category by @EwoutH in https://github.com/projectmesa/mesa/pull/2369
Add empty pull_request_template.md to enable PR template chooser by @EwoutH in https://github.com/projectmesa/mesa/pull/2409
remove deprecated HexGrid class by @quaquel in https://github.com/projectmesa/mesa/pull/2441
rename makeplotmeasure to makeplotcomponent and add some kwargs by @quaquel in https://github.com/projectmesa/mesa/pull/2446

New Contributors

@stephenfmann made their first contribution in https://github.com/projectmesa/mesa/pull/2154
@ENUMERA8OR made their first contribution in https://github.com/projectmesa/mesa/pull/2160
@rmhopkins4 made their first contribution in https://github.com/projectmesa/mesa/pull/2214
@vitorfrois made their first contribution in https://github.com/projectmesa/mesa/pull/2084
@OrenBochman made their first contribution in https://github.com/projectmesa/mesa/pull/2118

Full Changelog: https://github.com/projectmesa/mesa/compare/v2.4.0...v3.0.0

Scientific Software - Peer-reviewed - Python
Published by EwoutH about 1 year ago

Mesa 3 - Mesa 3.0 Release Candidate

Highlights

We're releasing the Mesa 3.0 Release Candidate, ready for final testing before we release Mesa 3.0 later this week!

In this last 3.0 pre-release, the visualisation has been thoroughly updated, with a brand new API. Visualizing the experimental Cell Space, including PropertyLayers and hexogonal grids, is now also supported.

We're still working very active on the visualisation, so we have marked that experimental for Mesa 3.0. We will stabilize SolaraViz in Mesa 3.1.

Any feedback and last-minute bug reports are welcome here.

What's Changed

⚠️ Breaking changes

Viz: Refactor Matplotlib plotting by @quaquel in https://github.com/projectmesa/mesa/pull/2430
api reorganization by @quaquel in https://github.com/projectmesa/mesa/pull/2447 ### 🧪 Experimental features
Mark SolaraViz as experimental for Mesa 3.0 by @EwoutH in https://github.com/projectmesa/mesa/pull/2459 ### 🛠 Enhancements made
expand ax.scatter kwargs that can be used by @quaquel in https://github.com/projectmesa/mesa/pull/2445 ### 🐛 Bugs fixed
Fix #2452 - handle solara viz model params better by @Corvince in https://github.com/projectmesa/mesa/pull/2454
Update MoneyModel.py by @quaquel in https://github.com/projectmesa/mesa/pull/2458 ### 🔍 Examples updated
Updates to Epstein example by @quaquel in https://github.com/projectmesa/mesa/pull/2429
Update examples to use updated space drawing by @quaquel in https://github.com/projectmesa/mesa/pull/2442 ### 📜 Documentation improvements
Update wolf-sheep png and fix typo in file name by @quaquel in https://github.com/projectmesa/mesa/pull/2444
Include main examples readme in docs by @quaquel in https://github.com/projectmesa/mesa/pull/2448
remove how-to guide and update docs in places by @quaquel in https://github.com/projectmesa/mesa/pull/2449 ### 🔧 Maintenance
remove deprecated HexGrid class by @quaquel in https://github.com/projectmesa/mesa/pull/2441
rename makeplotmeasure to makeplotcomponent and add some kwargs by @quaquel in https://github.com/projectmesa/mesa/pull/2446

Full Changelog: https://github.com/projectmesa/mesa/compare/v3.0.0b2...v3.0.0rc0

Scientific Software - Peer-reviewed - Python
Published by EwoutH about 1 year ago

Mesa 3 - Mesa 3.0 beta 2

Highlights

Mesa 3.0 beta 2 includes major work on the example models, docs, a new tutorial and visualisation.

The included example models are now part of the Mesa package itself and directly importable, using: Python from mesa.examples import BoidFlockers, BoltzmannWealthModel, ConwaysGameOfLife, ... The advanced examples were also restructured and cleaned up.

The tutorial was completely rewritten for Mesa 3.0, including it's latest features and practices. Many of our other docs also received some love, and almost everything is now ready for Mesa 3.0.

A new feature to remove all agents from the model was added, and the visualisation now supports drawing the experimental discrete spaces in both matplotlib and altair. All agents which are in a space can now conveniently be accessed with .agents.

The rarely used mesa startproject cookiecutter feature was removed. We updated our best-practice guide to include how to structure a modern Mesa project, which is now very straightforward.

What's Changed

⚠️ Breaking changes

remove cookiecutter by @quaquel in https://github.com/projectmesa/mesa/pull/2421 ### 🧪 Experimental features
Add support for drawing discrete grids by @quaquel in https://github.com/projectmesa/mesa/pull/2386
Altair spaces by @quaquel in https://github.com/projectmesa/mesa/pull/2397 ### 🎉 New features added
removeallagents method added to model by @quaquel in https://github.com/projectmesa/mesa/pull/2394
Pass through model.rgn in agent analogous to model.random by @quaquel in https://github.com/projectmesa/mesa/pull/2400
add agents property to all spaces by @quaquel in https://github.com/projectmesa/mesa/pull/2418 ### 🛠 Enhancements made
update_tutorial environment by @tpike3 in https://github.com/projectmesa/mesa/pull/2411 ### 🐛 Bugs fixed
Fix for mistaken removal of drawgrid by @quaquel in https://github.com/projectmesa/mesa/pull/2398
fixes weakref bug in shuffe_do by @quaquel in https://github.com/projectmesa/mesa/pull/2399 ### 🔍 Examples updated
refactor: Simplify Schelling code by @rht in https://github.com/projectmesa/mesa/pull/2353
Move examples into mesa by @Corvince in https://github.com/projectmesa/mesa/pull/2387
Explicitly test basic examples by @quaquel in https://github.com/projectmesa/mesa/pull/2390
Make example import absolute by @quaquel in https://github.com/projectmesa/mesa/pull/2402
Cleanup and restructure EpsteinCivilViolence and PdGrid examples by @EwoutH in https://github.com/projectmesa/mesa/pull/2408
Reorganize advanced examples: wolfsheep and sugarscapeg1mt by @quaquel in https://github.com/projectmesa/mesa/pull/2410
reactivate ruff for advanced examples and include them in tests by @quaquel in https://github.com/projectmesa/mesa/pull/2414 ### 📜 Documentation improvements
Include examples in readthedocs (port) by @EwoutH in https://github.com/projectmesa/mesa/pull/2392
Update into_tutorial by @tpike3 in https://github.com/projectmesa/mesa/pull/2372
Update Schelling Readme.md by @quaquel in https://github.com/projectmesa/mesa/pull/2406
Update Conway example by @quaquel in https://github.com/projectmesa/mesa/pull/2403
Boltzman readme by @quaquel in https://github.com/projectmesa/mesa/pull/2405
Update Readme.md of Boid flockers by @quaquel in https://github.com/projectmesa/mesa/pull/2404
add advanced examples to rtd by @quaquel in https://github.com/projectmesa/mesa/pull/2413
Tutorial Improvements by @tpike3 in https://github.com/projectmesa/mesa/pull/2415
space: Add note that Grids are maintenance only by @EwoutH in https://github.com/projectmesa/mesa/pull/2420
Migration guide: Update automatic unique_id assignment examples by @EwoutH in https://github.com/projectmesa/mesa/pull/2419
Update docstring of SimEvent by @quaquel in https://github.com/projectmesa/mesa/pull/2417 ### 🔧 Maintenance
Add empty pull_request_template.md to enable PR template chooser by @EwoutH in https://github.com/projectmesa/mesa/pull/2409

Full Changelog: https://github.com/projectmesa/mesa/compare/v3.0.0b1...v3.0.0b2

Scientific Software - Peer-reviewed - Python
Published by EwoutH about 1 year ago

Mesa 3 - Mesa 3.0 beta 1

Highlights

Mesa 3.0 beta 1 is our last beta release before the Mesa 3.0 stable release. We are restructuring our examples and have move 9 core examples from mesa-examples to mesa itself (#2358). The 5 basic examples are now directly importable (#2381): Python from examples.basic import BoidFlockers, BoltzmannWealthModel, ConwaysGameOfLife, Schelling, VirusOnNetwork The 5 basic examples will always use stable Mesa features, we are also working on 4 more advanced example which can also include experimental features.

All our core examples can now be viewed in the examples folder. mesa-examples will continue to exists for user showcases. We're also working on making the examples visible in the ReadtheDocs (#2382) and on an website (mesa-examples#139). Follow all our work on the examples in this tracking issue #2364.

Furthermore, the visualizations are improved by making visualization elements scalable and more clearly labeling the plots, and the Model now has an rng argument for an SPEC 7 compliant NumPy random number generator (#2352).

What's Changed

⚠️ Breaking changes

replace model with random in AgentSet init by @quaquel in https://github.com/projectmesa/mesa/pull/2350 ### 🧪 Experimental features
cell space: Add convenience properties for grid width and height by @quaquel in https://github.com/projectmesa/mesa/pull/2348
Bugfix for deepcopy / pickling discrete spaces by @quaquel in https://github.com/projectmesa/mesa/pull/2378 ### 🎉 New features added
Move core example models back (v2) by @EwoutH in https://github.com/projectmesa/mesa/pull/2358
Add Model.rng for SPEC-7 compliant numpy random number generation by @quaquel in https://github.com/projectmesa/mesa/pull/2352 ### 🛠 Enhancements made
use GridDraggable instead of Column in SolaraViz by @wang-boyu in https://github.com/projectmesa/mesa/pull/2344
update legend, xlabel & format of matplotlib plots by @wang-boyu in https://github.com/projectmesa/mesa/pull/2346
init.py: Import mesa.experimental by @EwoutH in https://github.com/projectmesa/mesa/pull/2374
Importable examples by @Corvince in https://github.com/projectmesa/mesa/pull/2381 ### 🐛 Bugs fixed
experimental init: Fix Solara import by making it lazy by @EwoutH in https://github.com/projectmesa/mesa/pull/2357
fix: pass model.random to schedulers by @quaquel in https://github.com/projectmesa/mesa/pull/2359
fix: register agent after creating unique_id and pos attributes by @wang-boyu in https://github.com/projectmesa/mesa/pull/2368
solara: viz tutorial: fix histogram code by @Corvince in https://github.com/projectmesa/mesa/pull/2379 ### 🔍 Examples updated
Cleanup and restructure basic example models by @EwoutH in https://github.com/projectmesa/mesa/pull/2365
Ruff basic examples by @EwoutH in https://github.com/projectmesa/mesa/pull/2370 ### 📜 Documentation improvements
Update migration_guide.md by @quaquel in https://github.com/projectmesa/mesa/pull/2347 ### 🔧 Maintenance
Code coverage: ignore experimental and visualization by @Corvince in https://github.com/projectmesa/mesa/pull/2361
add codecov token, fixes #2363 by @Corvince in https://github.com/projectmesa/mesa/pull/2366
add test_time back by @quaquel in https://github.com/projectmesa/mesa/pull/2367
Release notes: Add example category by @EwoutH in https://github.com/projectmesa/mesa/pull/2369

Full Changelog: https://github.com/projectmesa/mesa/compare/v3.0.0b0...v3.0.0b1

Scientific Software - Peer-reviewed - Python
Published by jackiekazil about 1 year ago

Mesa 3 - Mesa 3.0 beta 0

Highlights

We're proud to release the first Mesa 3.0 beta! This pre-release announces that we're ready for Mesa 3.0 to be tested by all our regular users. We try to not making breaking changes anymore, but focus on resolving bugs and imperfections.

In this beta, not so much has changed as in the alphas (we're stabilizing, that's a good sign), but there are still a few notable things: - Agents now have to be initialized without their unique_id. See #2328 and the Migration guide. - PropertyLayers can now be visualized! See #2336 for details and some examples, and mesa-examples#214 as a simple example model. - We reduced the core dependencies of Mesa, so that's a lighter and simpler install. You can now use extras to install the dependencies, for example add [viz] to install all visualisation dependencies: pip install -U --pre mesa[viz]. See #2265 for details. - The Mesa Overview as fully updated for 3.0. We highly recommend reading though it! - We made some more progress on the experimental Cell Space, adding movement and integrating the PropertyLayer. Among others, Agents have nu initial movement capabilities for grids. Development continues during the betas and

We plan to release one or two more beta's in the coming weeks, and tag a release candidate and Mesa 3.0 late October. In the v3.0 milestone are the critical items on our todo-list.

You can install this pre-release as usual with:

bash pip install --upgrade --pre mesa We're very curious what you think, try it out and ask any questions or share any feedback here!

What's Changed

⚠️ Breaking changes

update Agent.__init__ to remove deprecation warning by @quaquel in https://github.com/projectmesa/mesa/pull/2328 ### 🎉 New features added
Visualize PropertyLayers by @EwoutH in https://github.com/projectmesa/mesa/pull/2336 ### 🧪 Experimental features
Encapsulate cell movement in properties by @quaquel in https://github.com/projectmesa/mesa/pull/2333
experimental: Integrate PropertyLayers into cell space by @EwoutH in https://github.com/projectmesa/mesa/pull/2319
Generalize CellAgent by @Corvince in https://github.com/projectmesa/mesa/pull/2292 ### 🛠 Enhancements made
Reduce core dependencies, split in optional dependencies by @EwoutH in https://github.com/projectmesa/mesa/pull/2265 ### 🐛 Bugs fixed
viz: stop running and disable buttons when model.running is False by @wang-boyu in https://github.com/projectmesa/mesa/pull/2332 ### 📜 Documentation improvements
docs: Update overview for Mesa 3.0 by @EwoutH in https://github.com/projectmesa/mesa/pull/2317
Readthedocs: Add version switch and update URL by @EwoutH in https://github.com/projectmesa/mesa/pull/2324 ### 🔧 Maintenance
tests: Resolve warnings by removing scheduler and updating arguments by @EwoutH in https://github.com/projectmesa/mesa/pull/2329
add super call to Model and remove self.schedule by @quaquel in https://github.com/projectmesa/mesa/pull/2334 ### Other changes
Deprecate initialize_data_collector by @EwoutH in https://github.com/projectmesa/mesa/pull/2327

Full Changelog: https://github.com/projectmesa/mesa/compare/v3.0.0a5...v3.0.0b0

Scientific Software - Peer-reviewed - Python
Published by EwoutH about 1 year ago

Mesa 3 - v2.4.0

Highlights

Mesa 2.4.0 brings several key improvements from the upcoming 3.0 series, while maintaining compatibility with existing Mesa 2.x models.

The DataCollector now supports collecting data from specific Agent subclasses using the new agenttype_reporters parameter (#2300). This allows collecting different metrics for different agent types. For example:

python self.datacollector = DataCollector( agenttype_reporters={ Wolf: {"sheep_eaten": "sheep_eaten"}, Sheep: {"wool": "wool_amount"} } )

The AgentSet class, which underpins model.agents, has received major enhancements: - A new groupby() method to split agents into groups (#2220) - An agg() method to quickly compute aggregate values (#2266) - A faster shuffle_do() method for more efficient random agent activation (#2283) - The select() method now allows choosing a fraction of agents (#2253) - The do() method can now take any callable function, not just string method names (#2219)

Other notable improvements include: - The Model class now exposes an agents_by_type property for easier access to agents of specific types (#2267) - Performance enhancements for Model.agents (#2251) - The AgentSet.get() method now handles missing values with optional default value (#2279)

This release also fixes a bug in the Grid's move_agent_to_one_of method with selection="closest", which previously selected locations deterministically instead of randomly (#2118).

Finally, we've made significant documentation improvements, including the addition of a new Migration guide to help users transition to future Mesa versions (#2257).

What's Changed

🎉 New features added

Add AgentSet.groupby by @quaquel in #2220
AgentSet: Add agg method by @EwoutH in #2266
GroupBy: Add count and agg methods by @EwoutH in #2290
datacollector: Allow collecting data from Agent (sub)classes by @EwoutH in #2300
Add optimized shuffle_do() method to AgentSet by @EwoutH in #2283

🛠 Enhancements made

Allow AgentSet.do() to take Callable function by @quaquel in #2219
Split AgentSet into map and do to separate return types by @quaquel in #2237
Performance enhancements for Model.agents by @quaquel in #2251
AgentSet: Allow selecting a fraction of agents in the AgentSet by @EwoutH in #2253
Model: Replace get_agents_of_type method with agents_by_type property by @EwoutH in #2267
Add default values and missing value handling to agentset.get by @quaquel in #2279

🐛 Bugs fixed

Jupyter_viz: Allow measures to be None by @EwoutH in #2163
Fix deterministic behavior in move_agent_to_one_of with selection="closest" by @OrenBochman in #2118

📜 Documentation improvements

Contribution: Add "I have no idea where to start" section by @EwoutH in #2258
Write initial Mesa Migration guide by @EwoutH in #2257
Docs: Fix broken relative links by removing .html suffix by @EwoutH in #2274
Readthedocs: Don't let notebook failures pass silently by @EwoutH in #2276
update migration guide to describe solaraviz updates by @Corvince in #2297
Migration Guide: Add Model initialization requirement and automatic Agent.unique_id assignment by @EwoutH in #2302

🔧 Maintenance

make typing behavior of AgentSet.get explicit by @quaquel in #2293

Full Changelog: https://github.com/projectmesa/mesa/compare/v2.3.4...v2.4.0

Scientific Software - Peer-reviewed - Python
Published by EwoutH over 1 year ago

Mesa 3 - v3.0 alpha 5 (pre-release)

Highlights

Mesa v3.0 alpha 5 release contains many quality of life updates, a big new feature for the DataCollector and a major deprecation.

The entire mesa.time module, including all schedulers, has been deprecated (#2306). Users are encouraged to transition to AgentSet functionality for more flexible and explicit agent activation patterns. Check the migration guide on how to upgrade.

python self.datacollector = DataCollector( agenttype_reporters={ Wolf: {"sheep_eaten": "sheep_eaten"}, Sheep: {"wool": "wool_amount"} } )

Furthermore, a new shuffle_do() method for AgentSets provides a faster way to perform shuffle().do() (#2283). The GroupBy class gained count() and agg() methods to count the number of agents in groups and aggregate variables of them (#2290).

In the experimental Cell Space, the CellCollection.select method was updated to use at_most instead of n, aligning with the AgentSet API (#2307). Cell connections in grids and networks are now public and named for more intuitive agent movements (#2296). Additionally, the Cell class now features a dedicated neighborhood property for direct neighbors (default radius=1) and a get_neighborhood method for larger radii (#2309).

Finally, SolaraViz received updates improving its interface and performance (#2299, #2304). The Model class initialization process was simplified by moving random seed and random object creation to __init__ (#1940). Documentation has been extensively updated, including enforcing Google docstrings (#2294) and reorganizing the API documentation (#2298) for better clarity and navigation.

While the Mesa 3.0 timeline is still being discussed, we're aiming at the first Mesa 3.0 beta in October followed by a stable release in November. Testing new features and sharing feedback is appreciated!

What's Changed

🎉 New features added

GroupBy: Add count and agg methods by @EwoutH in https://github.com/projectmesa/mesa/pull/2290
datacollector: Allow collecting data from Agent (sub)classes by @EwoutH in https://github.com/projectmesa/mesa/pull/2300
Add optimized shuffle_do() method to AgentSet by @EwoutH in https://github.com/projectmesa/mesa/pull/2283 ### 🛠 Enhancements made
SolaraViz Updates by @Corvince in https://github.com/projectmesa/mesa/pull/2299
Solara viz: use_task for non-threaded continuous play by @Corvince in https://github.com/projectmesa/mesa/pull/2304 ### 🧪 Experimental features
Make cell connections public and named by @Corvince in https://github.com/projectmesa/mesa/pull/2296
Update to CellCollection.select by @quaquel in https://github.com/projectmesa/mesa/pull/2307
Have a dedicated neighborhood property and a get_neighborhood method on Cell by @quaquel in https://github.com/projectmesa/mesa/pull/2309 ### 📜 Documentation improvements
Enforce google docstrings by @quaquel in https://github.com/projectmesa/mesa/pull/2294
Api docs by @quaquel in https://github.com/projectmesa/mesa/pull/2298
update migration guide to describe solaraviz updates by @Corvince in https://github.com/projectmesa/mesa/pull/2297
Migration Guide: Add Model initialization requirement and automatic Agent.unique_id assignment by @EwoutH in https://github.com/projectmesa/mesa/pull/2302
Deprecate Time module and all its Schedulers by @EwoutH in https://github.com/projectmesa/mesa/pull/2306
introtutorial: Don't initialize agents with an uniqueid by @EwoutH in https://github.com/projectmesa/mesa/pull/2315
Migration guide: Intro, upgrade strategy, model.agents, headers by @EwoutH in https://github.com/projectmesa/mesa/pull/2314 ### 🔧 Maintenance
make typing behavior of AgentSet.get explicit by @quaquel in https://github.com/projectmesa/mesa/pull/2293
model: Move random seed and random to init by @rht in https://github.com/projectmesa/mesa/pull/1940
Remove schedulers from benchmark models. by @quaquel in https://github.com/projectmesa/mesa/pull/2308

Full Changelog: https://github.com/projectmesa/mesa/compare/v3.0.0a4...v3.0.0a5

Scientific Software - Peer-reviewed - Python
Published by EwoutH over 1 year ago

Mesa 3 - v3.0 alpha 4 (pre-release)

Highlights

Mesa 3.0.0a4 contains two major breaking changes: 1. The Agent's unique_id is now automatically assigned, so doesn't need to be passed to the Agent class anymore. In a subclassed custom Agent, like normally used, this now looks like this: ```diff class Wolf(Agent): - def init(self, uniqueid, model, energy=None): + def _init(self, model, energy=None): # When initializing the super class (Agent), passing unique_id isn't needed anymore - super().init(unique_id, model) + super().init__(model)

- wolf = Wolf(unique_id, model)
+ wolf = Wolf(model)
```
Example models were updated in [mesa-examples#194](https://github.com/projectmesa/mesa-examples/pull/194), which shows more examples on how to update existing models.

Our visualisation API is being overhauled, to be more flexible and powerful. For more details, see #2278.
- An initial update to the tutorial was made in #2289 and is available here.
- An initial example model was updated in mesa-examples#195, and more examples will be updated in mesa-examples#195.
- The old SolaraViz API is still available at mesa.experimental, but might be removed in future releases.

Furthermore, the AgentSet has a new agg method to quickly get an aggerate value (for example min_energy = model.agents.agg("energy", min)) (#2266), The Model get_agents_of_type function is replaced by directly exposing the agents_by_type property (which can be accessed as a dict) (#2267, mesa-examples#190) and the AgentSet get() methods can now handle missing values by replacing it with a default value (#2279).

Finally, it fixes a bug in which the Grid's move_agent_to_one_of method with selection="closest" selected a location deterministically, instead of randomly (#2118).

What's Changed

⚠️ Breaking changes

move solara_viz back to experimental by @Corvince in https://github.com/projectmesa/mesa/pull/2278
track unique_id automatically by @quaquel in https://github.com/projectmesa/mesa/pull/2260 ### 🎉 New features added
AgentSet: Add agg method by @EwoutH in https://github.com/projectmesa/mesa/pull/2266
Implement new SolaraViz API by @Corvince in https://github.com/projectmesa/mesa/pull/2263 ### 🛠 Enhancements made
Model: Replace get_agents_of_type method with agents_by_type property by @EwoutH in https://github.com/projectmesa/mesa/pull/2267
add default SolaraViz by @Corvince in https://github.com/projectmesa/mesa/pull/2280
Simplify ModelController by @Corvince in https://github.com/projectmesa/mesa/pull/2282
Add default values and missing value handling to agentset.get by @quaquel in https://github.com/projectmesa/mesa/pull/2279 ### 🐛 Bugs fixed
Fix deterministic behavior in move_agent_to_one_of with selection="closest" by @OrenBochman in https://github.com/projectmesa/mesa/pull/2118 ### 📜 Documentation improvements
docs: Fix Visualization Tutorial (main branch) by @EwoutH in https://github.com/projectmesa/mesa/pull/2271
Docs: Fix broken relative links by removing .html suffix by @EwoutH in https://github.com/projectmesa/mesa/pull/2274
Readthedocs: Don't let notebook failures pass silently by @EwoutH in https://github.com/projectmesa/mesa/pull/2276
Update viz tutorial to the new API by @Corvince in https://github.com/projectmesa/mesa/pull/2289 ### 🔧 Maintenance
Resolve multiprocessing warning, state Python 3.13 support by @rht in https://github.com/projectmesa/mesa/pull/2246

New Contributors

@OrenBochman made their first contribution in https://github.com/projectmesa/mesa/pull/2118

Full Changelog: https://github.com/projectmesa/mesa/compare/v3.0.0a3...v3.0.0a4

Scientific Software - Peer-reviewed - Python
Published by EwoutH over 1 year ago

Mesa 3 - v2.3.4

Highlights

Two fixes in our docs: The visualization tutorial started using an example model that wasn't compatible with Mesa 2.x anymore, and some relative links were broken. This release fixes both.

What's Changed

📜 Documentation improvements

docs: Fix Visualization Tutorial (2.x branch) by @EwoutH in https://github.com/projectmesa/mesa/pull/2272
Docs: Fix broken relative links by removing .html suffix by @EwoutH in https://github.com/projectmesa/mesa/pull/2274

Full Changelog: https://github.com/projectmesa/mesa/compare/v2.3.3...v2.3.4

Scientific Software - Peer-reviewed - Python
Published by EwoutH over 1 year ago

Mesa 3 - v2.3.3

Highlights

Mesa v2.3.3 is a small patch release with documentation and maintenance updates backported from our main branch.

We do have included one feature as preview for Mesa 3.0: The AgentSet got a convenient set method to quickly set a variable value to (a subset of) agents. See #2254 for some examples.

What's Changed

🎉 New features added

AgentSet: Add set method by @EwoutH in https://github.com/projectmesa/mesa/pull/2254 ### 📜 Documentation improvements
Fix image on landing page of docs. by @jackiekazil in https://github.com/projectmesa/mesa/pull/2146
Replace links in docs - google group to matrix. by @jackiekazil in https://github.com/projectmesa/mesa/pull/2148
Add experimental features to documentation as per #2122 by @stephenfmann in https://github.com/projectmesa/mesa/pull/2154
Update visualisation docs by @EwoutH in https://github.com/projectmesa/mesa/pull/2162
Add original conference paper link to docs by @ENUMERA8OR in https://github.com/projectmesa/mesa/pull/2160
docs/conf.py: Use modern intersphinx_mapping format by @EwoutH in https://github.com/projectmesa/mesa/pull/2206
Contribution: Add "I have no idea where to start" section by @EwoutH in https://github.com/projectmesa/mesa/pull/2258

Full Changelog: https://github.com/projectmesa/mesa/compare/v2.3.2...v2.3.3

Scientific Software - Peer-reviewed - Python
Published by EwoutH over 1 year ago

Mesa 3 - v3.0 alpha 3 (pre-release)

Highlights

Developments toward Mesa 3.0 are steaming ahead, and our fourth alpha release is packed with features and updates - only 8 days after our third.

Mesa 3.0.0a3 contains one breaking change: We now automatically increase the steps counter by one at the beginning of each Model.steps() call. That means increasing steps by hand isn't necessary anymore.

The big new features is the experimental Voronoi grid that @vitorfrois implemented in #2084. It allows creating cells in a Voronoi layout as part of the experimental cell space. An example using it to model Cholera spread can be found here.

The AgentSet got a lot of love with two brand new methods: .groupby() to split in groups (#2220) and .set() to easily assign variables to all agents in that set (#2254). The select() method is improved by allowing to select at most a fraction of the agents (#2253), and we split the do() method in do() and map() to make a distinction between the return types (#2237).

Furthermore, we improved the performance of accessing Model.agents, squashed a bug in SolaraViz, started testing on Python 3.13 and added a new benchmark model.

Our example models also got more love: We removed the RandomActivation scheduler in 14 models and removed SimultaneousActivation in 3 models (examples#183). They now use the automatic step increase and AgentSet functionality. We started testing our GIS model in CI (examples#171) and resolved a lot of bugs in them (examples#172, help appreciated!).

Finally, we have two brand new examples: An Ant Colony Optimization model using an Ant System approach to the Traveling Salesman problem, a Mesa NetworkGrid, and a custom visualisation with SolaraViz (examples#157 by @zjost). The first example using the PropertyLayer was added, a very fast implementation of Conway's Game of Life (examples#182).

To help the transition to Mesa 3.0, we started writing a migration guide. Progress is tracked in #2233, feedback and help is appreciated! Finally, we also added a new section to our contributor guide to get new contributors up to speed.

This pre-release can be installed as always with pip install --pre mesa

What's Changed

⚠️ Breaking changes

model: Automatically increase steps counter by @EwoutH in https://github.com/projectmesa/mesa/pull/2223 ### 🧪 Experimental features
Voronoi Tessellation based Discrete Space by @vitorfrois in https://github.com/projectmesa/mesa/pull/2084 ### 🎉 New features added
Add AgentSet.groupby by @quaquel in https://github.com/projectmesa/mesa/pull/2220
AgentSet: Add set method by @EwoutH in https://github.com/projectmesa/mesa/pull/2254 ### 🛠 Enhancements made
Split AgentSet into map and do to separate return types by @quaquel in https://github.com/projectmesa/mesa/pull/2237
Performance enhancements for Model.agents by @quaquel in https://github.com/projectmesa/mesa/pull/2251
AgentSet: Allow selecting a fraction of agents in the AgentSet by @EwoutH in https://github.com/projectmesa/mesa/pull/2253 ### 🐛 Bugs fixed
SolaraViz: Reset components when params are changed by @rht in https://github.com/projectmesa/mesa/pull/2240 ### 📜 Documentation improvements
Contribution: Add "I have no idea where to start" section by @EwoutH in https://github.com/projectmesa/mesa/pull/2258
Write initial Mesa Migration guide by @EwoutH in https://github.com/projectmesa/mesa/pull/2257 ### 🔧 Maintenance
CI: Add test job for Python 3.13 by @EwoutH in https://github.com/projectmesa/mesa/pull/2173
Add pull request templates by @EwoutH in https://github.com/projectmesa/mesa/pull/2217
benchmarks: Add BoltzmannWealth model by @EwoutH in https://github.com/projectmesa/mesa/pull/2252
CI: Add optional dependency for examples by @EwoutH in https://github.com/projectmesa/mesa/pull/2261

New Contributors

@vitorfrois made their first contribution in https://github.com/projectmesa/mesa/pull/2084

Full Changelog: https://github.com/projectmesa/mesa/compare/v3.0.0a2...v3.0.0a3

Scientific Software - Peer-reviewed - Python
Published by EwoutH over 1 year ago

Mesa 3 - v3.0 alpha 2 (pre-release)

Highlights

In Mesa 3.0 alpha 2 (v3.0.0a2) we've done more clean-up in preparation for Mesa 3.0. We now require super().__init__() to run on initializing a Mesa model subclass and fixed a bug in our Solara space_drawer.

A new feature was added in #2219, which now also allows AgentSet.do() to take any callable function, instead of only a string referencing to an Agent method. The argument name was changed from method_name to method.

We're also working hard on our example models. All model warnings were resolved and we've replaced a lot of schedulers with simpler and more flexible AgentSet functionality. Checkout our open issues if you want to help improve our example models further!

You can update to this version as usual with pip install mesa --upgrade --pre.

What's Changed

⚠️ Breaking changes

Allow AgentSet.do() to take Callable function by @quaquel in https://github.com/projectmesa/mesa/pull/2219
Require Mesa models to be initialized with super().__init__() by @EwoutH in https://github.com/projectmesa/mesa/pull/2218
breaking: Add dependencies argument to custom space_drawer by @rht in https://github.com/projectmesa/mesa/pull/2209 ### 🧪 Experimental enhancement
devs/eventlist: Add repr method to print EventList pretty by @EwoutH in https://github.com/projectmesa/mesa/pull/2195 ### 📜 Documentation improvements
docs: Update Readme and tutorials to mention Mesa 3.0 pre-releases by @EwoutH in https://github.com/projectmesa/mesa/pull/2203 ### 🔧 Maintenance
CI: Let pytest treat warnings as errors for examples by @EwoutH in https://github.com/projectmesa/mesa/pull/2204
docs/conf.py: Use modern intersphinx_mapping format by @EwoutH in https://github.com/projectmesa/mesa/pull/2206

Full Changelog: https://github.com/projectmesa/mesa/compare/v3.0.0a1...v3.0.0a2

Scientific Software - Peer-reviewed - Python
Published by EwoutH over 1 year ago

Mesa 3 - v3.0 alpha 1 (pre-release)

Highlights

Mesa 3.0 alpha 1 (v3.0.0a1) is another step towards our next major version. This release introduces a name change from JupyterViz (jupyterviz) to SolaraViz (solaraviz), to better represent the tech stack being used. It also includes two bugfixes also present in 2.3.2.

What's Changed

⚠️ Breaking changes

viz: Combine code for rendering in browser and Jupyter by @rht in https://github.com/projectmesa/mesa/pull/2180
refactor: Rename jupyterviz namespace to solaraviz by @rht in https://github.com/projectmesa/mesa/pull/2188 ### 🛠 Enhancements made
Rename JupyterViz to SolaraViz by @rht in https://github.com/projectmesa/mesa/pull/2187 ### 🐛 Bugs fixed
fix: Render agent marker radius correctly by @rht in https://github.com/projectmesa/mesa/pull/2181
fix: Use model.schedule.steps -> mode.steps for batchrun by @rht in https://github.com/projectmesa/mesa/pull/2183 ### 📜 Documentation improvements
Add original conference paper link to docs by @ENUMERA8OR in https://github.com/projectmesa/mesa/pull/2160

New Contributors

@ENUMERA8OR made their first contribution in https://github.com/projectmesa/mesa/pull/2160

Full Changelog: https://github.com/projectmesa/mesa/compare/v3.0.0a0...v3.0.0a1

Scientific Software - Peer-reviewed - Python
Published by EwoutH over 1 year ago

Mesa 3 - v2.3.2

Highlights

Mesa 2.3.2 is a small patch release which fixes two bugs, one to the batch_run function still depending on schedule.steps, and one in the agent marker visualisation.

What's Changed

🐛 Bugs fixed

fix: Render agent marker radius correctly by @rht in https://github.com/projectmesa/mesa/pull/2181
fix: Use model.schedule.steps -> model.steps for batchrun by @rht in https://github.com/projectmesa/mesa/pull/2183

Full Changelog: https://github.com/projectmesa/mesa/compare/v2.3.1...v2.3.2

Scientific Software - Peer-reviewed - Python
Published by EwoutH over 1 year ago

Mesa 3 - v3.0 alpha 0 (pre-release)

Highlights

This is the first pre-release in the Mesa 3.0 series, which is still in active development. The v3.0.0a0 pre-release can help active Mesa developers help starting to test the latest features in their models.

Since it's in active development, more breaking changes may follow and it's not recommended for general usage.

There are two major breaking changes at this point: - The old visualisation is removed, in favor of the new, Solara based, Jupyter Viz. This was already available in the 2.3.x release series, but is now stabilized. Checkout out our new Visualization Tutorial. More examples and a migration guide will follow later in the Mesa 3.0 development. - The mesa.flat namespace is removed, since was not used very often.

Mesa 3.0 will require Python 3.10+.

This pre-release can be installed with pip install mesa --upgrade --pre.

What's Changed

⚠️ Breaking changes

Remove mesa.flat namespace by @rht in https://github.com/projectmesa/mesa/pull/2091
breaking: Remove visualization_old (mesa-viz-tornado) by @rht in https://github.com/projectmesa/mesa/pull/2133 ### 🎉 New features added
Set JupyterViz as stable by @rht in https://github.com/projectmesa/mesa/pull/2090 ### 🐛 Bugs fixed
Jupyter_viz: Allow measures to be None by @EwoutH in https://github.com/projectmesa/mesa/pull/2163
Jupyter Viz: Don't avoid interactive backend by @EwoutH in https://github.com/projectmesa/mesa/pull/2165 ### 📜 Documentation improvements
Fix image on landing page of docs. by @jackiekazil in https://github.com/projectmesa/mesa/pull/2146
Replace links in docs - google group to matrix. by @jackiekazil in https://github.com/projectmesa/mesa/pull/2148
Update visualisation docs by @EwoutH in https://github.com/projectmesa/mesa/pull/2162 ### 🔧 Maintenance
CI: Add weekly scheduled run to all CI workflows by @EwoutH in https://github.com/projectmesa/mesa/pull/2130
Drop support for Python 3.9, require Python >= 3.10 by @EwoutH in https://github.com/projectmesa/mesa/pull/2132
Add script to list unlabeled PR's since latest release by @rht in https://github.com/projectmesa/mesa/pull/2047

New Contributors

@stephenfmann made their first contribution in https://github.com/projectmesa/mesa/pull/2154

Full Changelog: https://github.com/projectmesa/mesa/compare/v2.3.1...v3.0.0a0

Scientific Software - Peer-reviewed - Python
Published by EwoutH over 1 year ago

Mesa 3 - v2.3.1

Highlights

Mesa 2.3.1 is a small patch release with a datacollector bug fixed and improved documentation.

What's Changed

🐛 Bugs fixed

datacollector: store separate snapshots of model data per step by @EwoutH in https://github.com/projectmesa/mesa/pull/2129 ### 📜 Documentation improvements
Add experimental features to documentation as per #2122 by @stephenfmann in https://github.com/projectmesa/mesa/pull/2154

New Contributors

@stephenfmann made their first contribution in https://github.com/projectmesa/mesa/pull/2154

Full Changelog: https://github.com/projectmesa/mesa/compare/v2.3.0...v2.3.1

Scientific Software - Peer-reviewed - Python
Published by EwoutH over 1 year ago

Mesa 3 - v2.3.0

Highlights

Mesa 2.3.0 is a big feature release and the last feature release before 3.0.

There are two main new features: - The experimental cell-centric discrete spaces, as added in #1994. It allows having cells with not only properties but also active behaviors: the CellAgent. Its inspired by NetLogo's patches but extend and generalize this concept further. - Full support for discrete event scheduling, as added in #2066. It allows scheduling events (like Agent actions) at any time, including non-integer timesteps.

There are a lot of other features: The Jupyter visualisation now supports easier way to specify sliders, NetworkGrid.get_neighbors() supports a radius, AgentSet.get() can retrieve multiple attributes and there are now benchmarks to track Mesa performance during development.

Finally, 2.3.0 stabilizes the AgentSet (including model.agents), making it the first experimental Mesa feature that is taken out of it's experimental phase.

Install this release with: pip install --upgrade mesa The Mesa 2.3.x-series supports Python 3.9 to 3.12. The next major release will require Python 3.10.

What's Changed

🧪 Experimental features

Add cell-centric discrete spaces (experimental) by @Corvince in https://github.com/projectmesa/mesa/pull/1994 ### 🎉 New features added
Add performance benchmarking scripts by @EwoutH in https://github.com/projectmesa/mesa/pull/1979
feat: Implement Slider class for JupyterViz by @rht in https://github.com/projectmesa/mesa/pull/1972
Stabilize AgentSet by @EwoutH in https://github.com/projectmesa/mesa/pull/2065
Support discrete event scheduling by @quaquel in https://github.com/projectmesa/mesa/pull/2066 ### 🛠 Enhancements made
JupyterViz: Automatically deduce display name from model class by @rht in https://github.com/projectmesa/mesa/pull/1975
Add radius argument to NetworkGrid.get_neighbors() by @EwoutH in https://github.com/projectmesa/mesa/pull/1973
Speedup of Agentset.shuffle by @quaquel in https://github.com/projectmesa/mesa/pull/2010
feat: Let mesa runserver detect server.py as fallback by @rht in https://github.com/projectmesa/mesa/pull/2015
JupyterViz: {Convert make_plot & prepare ColorCard} to become Solara component by @rht in https://github.com/projectmesa/mesa/pull/2020
new feature: AgentSet.get can retrieve one or more then one attribute by @quaquel in https://github.com/projectmesa/mesa/pull/2044
Update CODEOFCONDUCT.md to version 2+ of contrib covenant by @jackiekazil in https://github.com/projectmesa/mesa/pull/2052
Improve flocking benchmark by @coderbeta1 in https://github.com/projectmesa/mesa/pull/2054
Remove JupyterViz Altair marker overlap for huge grid size by @rht in https://github.com/projectmesa/mesa/pull/2062
Add tooltip option to Altair chart by @FoFFolo in https://github.com/projectmesa/mesa/pull/2082
feat: Display model seed & allow user to specify it in JupyterViz by @rht in https://github.com/projectmesa/mesa/pull/2069
warn if placing already placed agent by @puer-robustus in https://github.com/projectmesa/mesa/pull/2083 ### 🐛 Bugs fixed
fix: Apply default value to slider by @rht in https://github.com/projectmesa/mesa/pull/2016
fix: Initialize model steps and _time during _new__ by @rht in https://github.com/projectmesa/mesa/pull/2026
fix: Use model.schedule only when it is not None by @rht in https://github.com/projectmesa/mesa/pull/2050
fix: Remove JupyterViz grid marker overlap for huge grid size by @rht in https://github.com/projectmesa/mesa/pull/2049
Make agent move to actual random closest position by @EwoutH in https://github.com/projectmesa/mesa/pull/2119 ### 📜 Documentation improvements
Improve readability of badges by @rht in https://github.com/projectmesa/mesa/pull/2009
More pythonic implementation of wolf sheep by @quaquel in https://github.com/projectmesa/mesa/pull/2011
Adding super().init() to MoneyModel tutorial by @sw23 in https://github.com/projectmesa/mesa/pull/2025
docs: Convert howto.rst -> howto.md via rst2myst by @rht in https://github.com/projectmesa/mesa/pull/2033
docs: Convert best-practices,overview,packages,mesa,index to .md via rst2myst by @rht in https://github.com/projectmesa/mesa/pull/2034
docs: Convert api/.rst -> api/.md via rst2myst by @rht in https://github.com/projectmesa/mesa/pull/2035
docs: Rewrite howto.md using ChatGPT for clarity and conciseness by @rht in https://github.com/projectmesa/mesa/pull/2037
docs: Corrected Contributing Guide Link to Ensure Accessibility by @sahusiddharth in https://github.com/projectmesa/mesa/pull/2057
Rename links to internal .rst files to .md by @rht in https://github.com/projectmesa/mesa/pull/2058
docs: improve introductory tutorial by @puer-robustus in https://github.com/projectmesa/mesa/pull/2087 ### 🔧 Maintenance
Quality of Life: Make codecov less meticulous by @Corvince in https://github.com/projectmesa/mesa/pull/1966
Add CI workflow for performance benchmarks by @EwoutH in https://github.com/projectmesa/mesa/pull/1983
tests: Resolve warnings by defining PropertyLayer dtypes by @EwoutH in https://github.com/projectmesa/mesa/pull/1987
benchmarks.yml: Fix PR branch checkout when triggered by comment by @EwoutH in https://github.com/projectmesa/mesa/pull/1998
Quality of life: automatically fix ruff errors by @Corvince in https://github.com/projectmesa/mesa/pull/2004
benchmarks.yml: Run on addition of label instead of comment by @EwoutH in https://github.com/projectmesa/mesa/pull/2002
ci: Move codespell to pre-commit by @rht in https://github.com/projectmesa/mesa/pull/2040
Schelling by @coderbeta1 in https://github.com/projectmesa/mesa/pull/2053
Move ruff lint settings into dedicated section by @Corvince in https://github.com/projectmesa/mesa/pull/2073
ci: Use uv pip for faster build by @rht in https://github.com/projectmesa/mesa/pull/2038
test: Remove place_agent duplicate warnings by @rht in https://github.com/projectmesa/mesa/pull/2086 ### Other changes
Minor edits to benchmarking code by @quaquel in https://github.com/projectmesa/mesa/pull/1985
build(deps): bump codecov/codecov-action from 3 to 4 by @dependabot in https://github.com/projectmesa/mesa/pull/2030
[pre-commit.ci] pre-commit autoupdate by @pre-commit-ci in https://github.com/projectmesa/mesa/pull/2029
tests: Speed up testbatchrun by @rht in https://github.com/projectmesa/mesa/pull/2039
Update benchmarks.yml by @Corvince in https://github.com/projectmesa/mesa/pull/2043
docs: Convert visualization .rst -> .md via rst2myst by @rht in https://github.com/projectmesa/mesa/pull/2036
docs: Convert CONTRIBUTING .rst -> .md via rst2myst by @rht in https://github.com/projectmesa/mesa/pull/2041
Correct wolf energy gained from eating sheep by @JackAtOmenApps in https://github.com/projectmesa/mesa/pull/2048
feat: Implement Altair version of grid visualization by @rht in https://github.com/projectmesa/mesa/pull/1991

New Contributors

@sw23 made their first contribution in https://github.com/projectmesa/mesa/pull/2025
@JackAtOmenApps made their first contribution in https://github.com/projectmesa/mesa/pull/2048
@coderbeta1 made their first contribution in https://github.com/projectmesa/mesa/pull/2054
@sahusiddharth made their first contribution in https://github.com/projectmesa/mesa/pull/2057
@FoFFolo made their first contribution in https://github.com/projectmesa/mesa/pull/2082
@puer-robustus made their first contribution in https://github.com/projectmesa/mesa/pull/2083

Full Changelog: https://github.com/projectmesa/mesa/compare/v2.2.4...2.3.0

Scientific Software - Peer-reviewed - Python
Published by EwoutH over 1 year ago

Mesa 3 - v2.3.0-rc1

Highlights

The 2.3.0-rc1 release is our first release candidate pre-release, meant to test all the new features and enhancement for the upcoming 2.3.0 release.

Finally, 2.3.0 stabilizes the AgentSet (including model.agents), making it the first experimental Mesa feature that is taken out of it's experimental phase.

Install this pre-release with: pip install --pre mesa We would love feedback before we release 2.3.0 stable in ~1 week.

What's Changed

🧪 Experimental features

Add cell-centric discrete spaces (experimental) by @Corvince in https://github.com/projectmesa/mesa/pull/1994 ### 🎉 New features added
Add performance benchmarking scripts by @EwoutH in https://github.com/projectmesa/mesa/pull/1979
feat: Implement Slider class for JupyterViz by @rht in https://github.com/projectmesa/mesa/pull/1972
Stabilize AgentSet by @EwoutH in https://github.com/projectmesa/mesa/pull/2065
Support discrete event scheduling by @quaquel in https://github.com/projectmesa/mesa/pull/2066 ### 🛠 Enhancements made
JupyterViz: Automatically deduce display name from model class by @rht in https://github.com/projectmesa/mesa/pull/1975
Add radius argument to NetworkGrid.get_neighbors() by @EwoutH in https://github.com/projectmesa/mesa/pull/1973
Speedup of Agentset.shuffle by @quaquel in https://github.com/projectmesa/mesa/pull/2010
feat: Let mesa runserver detect server.py as fallback by @rht in https://github.com/projectmesa/mesa/pull/2015
JupyterViz: {Convert make_plot & prepare ColorCard} to become Solara component by @rht in https://github.com/projectmesa/mesa/pull/2020
new feature: AgentSet.get can retrieve one or more then one attribute by @quaquel in https://github.com/projectmesa/mesa/pull/2044
Update CODEOFCONDUCT.md to version 2+ of contrib convenant by @jackiekazil in https://github.com/projectmesa/mesa/pull/2052
Improve flocking benchmark by @coderbeta1 in https://github.com/projectmesa/mesa/pull/2054
Remove JupyterViz Altair marker overlap for huge grid size by @rht in https://github.com/projectmesa/mesa/pull/2062
Add tooltip option to Altair chart by @FoFFolo in https://github.com/projectmesa/mesa/pull/2082
feat: Display model seed & allow user to specify it in JupyterViz by @rht in https://github.com/projectmesa/mesa/pull/2069
warn if placing already placed agent by @puer-robustus in https://github.com/projectmesa/mesa/pull/2083 ### 🐛 Bugs fixed
fix: Apply default value to slider by @rht in https://github.com/projectmesa/mesa/pull/2016
fix: Initialize model steps and _time during _new__ by @rht in https://github.com/projectmesa/mesa/pull/2026
fix: Use model.schedule only when it is not None by @rht in https://github.com/projectmesa/mesa/pull/2050
fix: Remove JupyterViz grid marker overlap for huge grid size by @rht in https://github.com/projectmesa/mesa/pull/2049 ### 📜 Documentation improvements
Improve readability of badges by @rht in https://github.com/projectmesa/mesa/pull/2009
More pythonic implementation of wolf sheep by @quaquel in https://github.com/projectmesa/mesa/pull/2011
Adding super().init() to MoneyModel tutorial by @sw23 in https://github.com/projectmesa/mesa/pull/2025
docs: Convert howto.rst -> howto.md via rst2myst by @rht in https://github.com/projectmesa/mesa/pull/2033
docs: Convert best-practices,overview,packages,mesa,index to .md via rst2myst by @rht in https://github.com/projectmesa/mesa/pull/2034
docs: Convert api/.rst -> api/.md via rst2myst by @rht in https://github.com/projectmesa/mesa/pull/2035
docs: Rewrite howto.md using ChatGPT for clarity and conciseness by @rht in https://github.com/projectmesa/mesa/pull/2037
docs: Corrected Contributing Guide Link to Ensure Accessibility by @sahusiddharth in https://github.com/projectmesa/mesa/pull/2057
Rename links to internal .rst files to .md by @rht in https://github.com/projectmesa/mesa/pull/2058
docs: improve introductory tutorial by @puer-robustus in https://github.com/projectmesa/mesa/pull/2087 ### 🔧 Maintenance
Quality of Life: Make codecov less meticulous by @Corvince in https://github.com/projectmesa/mesa/pull/1966
Add CI workflow for performance benchmarks by @EwoutH in https://github.com/projectmesa/mesa/pull/1983
tests: Resolve warnings by defining PropertyLayer dtypes by @EwoutH in https://github.com/projectmesa/mesa/pull/1987
benchmarks.yml: Fix PR branch checkout when triggered by comment by @EwoutH in https://github.com/projectmesa/mesa/pull/1998
Quality of life: automatically fix ruff errors by @Corvince in https://github.com/projectmesa/mesa/pull/2004
benchmarks.yml: Run on addition of label instead of comment by @EwoutH in https://github.com/projectmesa/mesa/pull/2002
ci: Move codespell to pre-commit by @rht in https://github.com/projectmesa/mesa/pull/2040
Schelling by @coderbeta1 in https://github.com/projectmesa/mesa/pull/2053
Move ruff lint settings into dedicated section by @Corvince in https://github.com/projectmesa/mesa/pull/2073
ci: Use uv pip for faster build by @rht in https://github.com/projectmesa/mesa/pull/2038
test: Remove place_agent duplicate warnings by @rht in https://github.com/projectmesa/mesa/pull/2086 ### Other changes
Minor edits to benchmarking code by @quaquel in https://github.com/projectmesa/mesa/pull/1985
build(deps): bump codecov/codecov-action from 3 to 4 by @dependabot in https://github.com/projectmesa/mesa/pull/2030
[pre-commit.ci] pre-commit autoupdate by @pre-commit-ci in https://github.com/projectmesa/mesa/pull/2029
tests: Speed up testbatchrun by @rht in https://github.com/projectmesa/mesa/pull/2039
Update benchmarks.yml by @Corvince in https://github.com/projectmesa/mesa/pull/2043
docs: Convert visualization .rst -> .md via rst2myst by @rht in https://github.com/projectmesa/mesa/pull/2036
docs: Convert CONTRIBUTING .rst -> .md via rst2myst by @rht in https://github.com/projectmesa/mesa/pull/2041
Correct wolf energy gained from eating sheep by @JackAtOmenApps in https://github.com/projectmesa/mesa/pull/2048
feat: Implement Altair version of grid visualization by @rht in https://github.com/projectmesa/mesa/pull/1991

New Contributors

@sw23 made their first contribution in https://github.com/projectmesa/mesa/pull/2025
@JackAtOmenApps made their first contribution in https://github.com/projectmesa/mesa/pull/2048
@coderbeta1 made their first contribution in https://github.com/projectmesa/mesa/pull/2054
@sahusiddharth made their first contribution in https://github.com/projectmesa/mesa/pull/2057
@FoFFolo made their first contribution in https://github.com/projectmesa/mesa/pull/2082
@puer-robustus made their first contribution in https://github.com/projectmesa/mesa/pull/2083

Full Changelog: https://github.com/projectmesa/mesa/compare/v2.2.4...2.3.0-rc1

Scientific Software - Peer-reviewed - Python
Published by EwoutH over 1 year ago

Mesa 3 - v2.2.5

What's Changed

🧪 Experimental features

solara_viz: Add borders around ContinuousSpace by @EwoutH in https://github.com/projectmesa/mesa/pull/1988 ### 🎉 New features added
Add performance benchmarking scripts by @EwoutH in https://github.com/projectmesa/mesa/pull/1979
feat: Implement Slider class for JupyterViz by @rht in https://github.com/projectmesa/mesa/pull/1972
new feature: AgentSet.get can retrieve one or more then one attribute by @quaquel in https://github.com/projectmesa/mesa/pull/2044 ### 🛠 Enhancements made
JupyterViz: Automatically deduce display name from model class by @rht in https://github.com/projectmesa/mesa/pull/1975
Add radius argument to NetworkGrid.get_neighbors() by @EwoutH in https://github.com/projectmesa/mesa/pull/1973
refactor: Remove dependence on model.schedule, add clock to Model by @rht in https://github.com/projectmesa/mesa/pull/1942
Speedup of Agentset.shuffle by @quaquel in https://github.com/projectmesa/mesa/pull/2010
feat: Let mesa runserver detect server.py as fallback by @rht in https://github.com/projectmesa/mesa/pull/2015
JupyterViz: {Convert make_plot & prepare ColorCard} to become Solara component by @rht in https://github.com/projectmesa/mesa/pull/2020 ### 🐛 Bugs fixed
Allow user models to assign Model.agents for now, but add warning by @quaquel in https://github.com/projectmesa/mesa/pull/1976
fix: Explicitly specify JupyterViz space view limits by @rht in https://github.com/projectmesa/mesa/pull/1984
fix: Reverse dict key and value for agentsbytype by @rht in https://github.com/projectmesa/mesa/pull/1996
Fix AgentSet inplace shuffle (and thus RandomActivation), add tests by @EwoutH in https://github.com/projectmesa/mesa/pull/2007
fix: Apply default value to slider by @rht in https://github.com/projectmesa/mesa/pull/2016
fix: Initialize model steps and _time during _new__ by @rht in https://github.com/projectmesa/mesa/pull/2026
fix: Use model.schedule only when it is not None by @rht in https://github.com/projectmesa/mesa/pull/2050 ### 📜 Documentation improvements
Improve readability of badges by @rht in https://github.com/projectmesa/mesa/pull/2009
More pythonic implementation of wolf sheep by @quaquel in https://github.com/projectmesa/mesa/pull/2011
Adding super().init() to MoneyModel tutorial by @sw23 in https://github.com/projectmesa/mesa/pull/2025
docs: Convert howto.rst -> howto.md via rst2myst by @rht in https://github.com/projectmesa/mesa/pull/2033
docs: Convert best-practices,overview,packages,mesa,index to .md via rst2myst by @rht in https://github.com/projectmesa/mesa/pull/2034
docs: Convert api/.rst -> api/.md via rst2myst by @rht in https://github.com/projectmesa/mesa/pull/2035
docs: Rewrite howto.md using ChatGPT for clarity and conciseness by @rht in https://github.com/projectmesa/mesa/pull/2037 ### 🔧 Maintenance
Quality of Life: Make codecov less meticulous by @Corvince in https://github.com/projectmesa/mesa/pull/1966
Add CI workflow for performance benchmarks by @EwoutH in https://github.com/projectmesa/mesa/pull/1983
tests: Resolve warnings by defining PropertyLayer dtypes by @EwoutH in https://github.com/projectmesa/mesa/pull/1987
benchmarks.yml: Fix PR branch checkout when triggered by comment by @EwoutH in https://github.com/projectmesa/mesa/pull/1998
Quality of life: automatically fix ruff errors by @Corvince in https://github.com/projectmesa/mesa/pull/2004
benchmarks.yml: Run on addition of label instead of comment by @EwoutH in https://github.com/projectmesa/mesa/pull/2002
ci: Move codespell to pre-commit by @rht in https://github.com/projectmesa/mesa/pull/2040 ### Other changes
Minor edits to benchmarking code by @quaquel in https://github.com/projectmesa/mesa/pull/1985
build(deps): bump codecov/codecov-action from 3 to 4 by @dependabot in https://github.com/projectmesa/mesa/pull/2030
[pre-commit.ci] pre-commit autoupdate by @pre-commit-ci in https://github.com/projectmesa/mesa/pull/2029
tests: Speed up testbatchrun by @rht in https://github.com/projectmesa/mesa/pull/2039
Update benchmarks.yml by @Corvince in https://github.com/projectmesa/mesa/pull/2043
docs: Convert visualization .rst -> .md via rst2myst by @rht in https://github.com/projectmesa/mesa/pull/2036
docs: Convert CONTRIBUTING .rst -> .md via rst2myst by @rht in https://github.com/projectmesa/mesa/pull/2041
Correct wolf energy gained from eating sheep by @JackAtOmenApps in https://github.com/projectmesa/mesa/pull/2048
feat: Implement Altair version of grid visualization by @rht in https://github.com/projectmesa/mesa/pull/1991

New Contributors

@sw23 made their first contribution in https://github.com/projectmesa/mesa/pull/2025
@JackAtOmenApps made their first contribution in https://github.com/projectmesa/mesa/pull/2048

Full Changelog: https://github.com/projectmesa/mesa/compare/v2.2.1...v2.2.5

Scientific Software - Peer-reviewed - Python
Published by tpike3 almost 2 years ago

Mesa 3 - v2.2.4

Highlights

Mesa v2.2.4 is a small but important bugfix release for the 2.2 release series. It fixes an essential bug in where agents weren't shuffled in the RandomActivation scheduler (effectively making it sequential activation)(#2007). It also fixes a small behaviour change in RandomActivationByType.agents_by_type() (#1996). Furthermore, this release adds an internal clock to the Model, which allows to use a Mesa model without a scheduler (using the AgentSet API)(#1942).

Updating from previous 2.2 releases is highly recommended, especially when using the RandomActivation scheduler.

What's Changed

🛠 Enhancements made

refactor: Remove dependence on model.schedule, add clock to Model by @rht in https://github.com/projectmesa/mesa/pull/1942 ### 🐛 Bugs fixed
Fix AgentSet inplace shuffle (and thus RandomActivation), add tests by @EwoutH and @quaquel in https://github.com/projectmesa/mesa/pull/2007
fix: Reverse dict key and value for agentsbytype by @rht in https://github.com/projectmesa/mesa/pull/1996

Full Changelog: https://github.com/projectmesa/mesa/compare/v2.2.3...v2.2.4

Scientific Software - Peer-reviewed - Python
Published by EwoutH almost 2 years ago

Mesa 3 - v2.2.3

Highlights

Mesa 2.2.3 is a small release with two improvements to the experimental Solara visualisation, on request of one of our contributors. No stable features have changed.

What's Changed

🧪 Experimental features

solara_viz: Add borders around ContinuousSpace by @EwoutH in https://github.com/projectmesa/mesa/pull/1988 ### 🐛 Bugs fixed
fix: Explicitly specify JupyterViz space view limits by @rht in https://github.com/projectmesa/mesa/pull/1984

Full Changelog: https://github.com/projectmesa/mesa/compare/v2.2.2...v2.2.3

Scientific Software - Peer-reviewed - Python
Published by EwoutH almost 2 years ago

Mesa 3 - v2.2.2

Highlights

Mesa 2.2.2 is a small bugfix release, for models in which users had defined Model.agents (self.agents in a Model (sub)class). This is deprecated, but for now allowed. See #1919 (comment).

What's Changed

🐛 Bugs fixed

Allow user models to assign Model.agents for now, but add warning by @quaquel in #1976

Full Changelog: https://github.com/projectmesa/mesa/compare/v2.2.1...v2.2.2

Scientific Software - Peer-reviewed - Python
Published by EwoutH almost 2 years ago

Mesa 3 - v2.2.1

Highlights

After the substantive 2.2.0 release we are releasing 2.2.1 which addresses a few bugs, unintended behaviors and a performance regression. #1960 makes sure agent addition and removal is handled correct, #1965 fixed an unintended behavior change in RandomActivationByType.agents_by_type and #1964 makes sure we're at least as fast as before 2.2.0, if not faster. The introduction tutorial is also extended with #1955.

We highly recommend updating to 2.2.1 if you're using 2.2.0. bash pip install --upgrade mesa

What's Changed

🧪 Experimental features

jupyter_viz: Implement multiline plot by @rht in https://github.com/projectmesa/mesa/pull/1941 ### 🛠 Enhancements made
make mesa runable without some dependencies by @Corvince in https://github.com/projectmesa/mesa/pull/1950
Improve performance of AgentSet and itercelllist_contents by @Corvince in https://github.com/projectmesa/mesa/pull/1964 ### 🐛 Bugs fixed
Bugfix in agentset to handle addition and removal correctly by @quaquel in https://github.com/projectmesa/mesa/pull/1960
Make RandomActivationByType.agentsbytype backward compatible by @quaquel in https://github.com/projectmesa/mesa/pull/1965 ### 📜 Documentation improvements
Refer to just Python instead of Python 3 by @rht in https://github.com/projectmesa/mesa/pull/1957
intro tutorial: Analysing model reporters by @EwoutH in https://github.com/projectmesa/mesa/pull/1955 ### 🔧 Maintenance
Migrate from setuptools to hatch by @rht in https://github.com/projectmesa/mesa/pull/1882
ci: Add tests for mesa-examples by @rht in https://github.com/projectmesa/mesa/pull/1956
refactor: Move Matplotlib-specific Solara components to separate file by @rht in https://github.com/projectmesa/mesa/pull/1943

Full Changelog: https://github.com/projectmesa/mesa/compare/v2.2.0...v2.2.1

Scientific Software - Peer-reviewed - Python
Published by EwoutH almost 2 years ago

Mesa 3 - v2.2.0

Highlights

This release incorporates several majors changes to Mesa. Notably, this provides two experimental features. (1) It reimagines Mesa's agent handling to have agents in the model class and store them in sets (you may submit feedback at https://github.com/projectmesa/mesa/discussions/1919). The intent is to make Mesa more efficient and give users more control over agent scheduling to allow for innumerable options. (2) It adds property layer and property grid so users can layer on multiple grids making Mesa and Geo-Mesa more similar (you may submit feedback at https://github.com/projectmesa/mesa/discussions/1932).

What's Changed

🧪 Experimental features

Introduce AgentSet class by @EwoutH in https://github.com/projectmesa/mesa/pull/1916
Reimplement schedulers to use AgentSet by @quaquel in https://github.com/projectmesa/mesa/pull/1926
Work around for initializing model._agent by @quaquel in https://github.com/projectmesa/mesa/pull/1928
space: Implement PropertyLayer and _PropertyGrid by @EwoutH in https://github.com/projectmesa/mesa/pull/1898

🛠 Enhancements made

Native support for multiple agent types by @EwoutH in https://github.com/projectmesa/mesa/pull/1894
Document empties property by @EwoutH in https://github.com/projectmesa/mesa/pull/1888
Add DiscreteEventScheduler by @EwoutH in https://github.com/projectmesa/mesa/pull/1890
space: Let move_agent choose from multiple positions by @EwoutH in https://github.com/projectmesa/mesa/pull/1920

🐛 Bugs fixed

Honor disabled space drawer option when rendering in the browser by @rlskoeser in https://github.com/projectmesa/mesa/pull/1907

📜 Documentation improvements

docs: Fix README.md inline code formatting by @rht in https://github.com/projectmesa/mesa/pull/1887
Add experimental warning to DiscreteEventScheduler by @EwoutH in https://github.com/projectmesa/mesa/pull/1924

🔧 Maintenance

ci: Speed up pip install by caching deps install output by @rht in https://github.com/projectmesa/mesa/pull/1885
[pre-commit.ci] pre-commit autoupdate by @pre-commit-ci in https://github.com/projectmesa/mesa/pull/1899
build(deps): bump actions/setup-python from 4 to 5 by @dependabot in https://github.com/projectmesa/mesa/pull/1904
Create release.yml file for automatic release notes generation by @EwoutH in https://github.com/projectmesa/mesa/pull/1925
Drop support for Python 3.8 by @rht in https://github.com/projectmesa/mesa/pull/1756

New Contributors

@quaquel made their first contribution in https://github.com/projectmesa/mesa/pull/1928

Full Changelog: https://github.com/projectmesa/mesa/compare/v2.1.5...v2.2.0

Scientific Software - Peer-reviewed - Python
Published by tpike3 almost 2 years ago

Mesa 3 - v2.1.3

2.1.3 (2023-11-5)

This release contains several improvements, fixes, and new features to the JupyterViz/Solara frontend. It's a patch release instead of a minor release because the JupyterViz frontend is still considered experimental.

Improvements

model: ensure model is initialized with random seed based #1814
space: check if position values are tuples #1831
datacollection: add agent collection by type, documentation, and tests #1838

Docs and Tutorial

tutorial: explain how to set up reporter for multiple agents #1717
docs: rename useful snippets to how to guide #1839

CI and WorkFlows

Release CI: update to run workflows on releases #1479
CI: Update GHA workflows with Python 3.12 #1840
update ruff version #1824, #1841
Ensure mesaviztornado>=0.1.2 #1860

Solara/JupyterViz

perf: increase speed of Solara render #1819
implement drawer for continuous space and refactor code #1830
fix: configure change handler for checkbox input #1844
fix: ensure playing starts after model param change #1851

Scientific Software - Peer-reviewed - Python
Published by tpike3 about 2 years ago

Mesa 3 - v2.1.2

This release contains fixes, and several improvements and new features to the JupyterViz/Solara frontend. It's a patch release instead of a minor release because the JupyterViz frontend is still considered experimental.

Improvements

perf: Access grid only once #1751
docs: compile notebooks at build time #1753
docs: Remove nbsphinx and explicit .ipynb suffix #1754
rtd: Use gruvbox-dark as style #1719
build(deps): bump actions/checkout from 3 to 4 #1790

Solara/JupyterViz

solara: Implement visualization for network grid #1767
Add support for select input type #1779
Add step count display to JupyterViz #1775
Simplify solara code #1786
Add docstring for jupyterviz makeuserinput that documents supported inputs #1784
Revise, test, & document JupyterViz options for drawing agent space #1783
Add UserInputs component #1788
Fix: Remove dict merge operator, python 3.8 compat #1793
feat: Add reset button to JupyterViz #1795
Add support for solara.Checkbox user input #1798
viz tutorial: Update custom plot to reflect new code #1799
fix: Don't continue playing when a model is reset #1796
Docker: Update to use Solara viz #1757

Refactors

Move viz stuff to mesa-viz-tornado Git repo #1746
simplify get neighborhood #1760
remove attrgetter performance optimization #1809

Fixes

fix: Add Matplotlib as dependency #1747
fix install for visualization tutorial in colab #1752
fix: Allow multiple connections in Solara #1759
Revert "Ensure sphinx>=7" #1762
fix README pic to remove line on left side #1763
space: Ensure get_neighborhood output & cache are immutable #1780
fix: Use .pytemplate for name for cookiecutter #1785
HISTORY.rst: Correct neighbor_iter() replacement in 2.0.0 #1807
docs: Always link to stable version #1810
Remove excludenonevalues #1813

Scientific Software - Peer-reviewed - Python
Published by rht over 2 years ago

Mesa 3 - v2.1.1

This release improves the introductory and visualization tutorial. Ensures both are Google Colab compatible with working badges.

Changes: - Update introtutorial to warn users to ensure up to date version, and make colab compatible #1739, #1744 - Improve new/experimental Solara based visualization to ensure pause button works #1745 - Fix bug in space.py -> getheading() #1739

Scientific Software - Peer-reviewed - Python
Published by rht over 2 years ago

Mesa 3 - v2.1.0 Youngtown

This release creates mesa.experimental namespace, this solves the issue that PyPI release will not allow git-based install.

Users should read the Mesa 2.0.0 release note, as this contains the details about the breaking changes and other major changes that were part of Mesa 2.0 release.

The mesa.experimental currently consists of JupyterViz, a new visualization framework that can run on a Jupyter notebook as well as standalone.

Changes: * Creates mesa.experimental namespace #1736 * Fix Ruff lint error #1737 * Update permissions for PyPI #1732

Scientific Software - Peer-reviewed - Python
Published by rht over 2 years ago

Mesa 3 - v2.0.0 Wellton

Special notes

Mesa 2.0 includes: * an experimental pure python user interface/ visualization that is also jupyter compatible please see the visualization tutorial_ * several breaking changes that provide significant improvements to Mesa.

.. visualization tutorial: https://mesa.readthedocs.io/en/latest/tutorials/visualizationtutorial.html Breaking Changes:

space: change coord_iter to return (content,(x,y)) instead of (content, x,y); this reduces known errors of scheduler to grid mismatch #1566, #1723
space: change NetworkGrid get_neighbors to get_neighborhood; improves performance #1542
space: raise exception when pos is out of bounds in Grid.get_neighborhood #1524
space: remove deprecations (#1520, #1687, #1688):
- find_empty(): convert this to move_to_empty()
- num_agents: removed parameter from move_to_empty()
- position_agent(): convert this to place_agent
- neighbor_iter(): convert this to iter_neighborhood()
batchrunner: remove deprecations #1627
- class BatchRunner and class BatchRunnerMP: convert these to batch_run()
- Please see this batch_run() example_ if you would like to see an an implementation.
visualization: easier visualization creation #1693
- UserSettableParameter(['number', 'slider','checkbox', 'choice', 'StaticText']): convert to NumberInput , Slider, CheckBox, Choice, StaticText
- Please see this visualization example_ if you would like to see an implementation.

.. batchrun() example: https://github.com/projectmesa/mesa-examples/blob/db2ec0383eb3b1868e91c828101e84cce97bbb63/examples/bankreserves/batchrun.py#L188-L221 .. visualization example: https://github.com/projectmesa/mesa-examples/blob/db2ec0383eb3b1868e91c828101e84cce97bbb63/examples/boltzmannwealthmodel/boltzmannwealth_model/server.py#L25-L32.)

New Features:

datacollector: can now handle data collection by agent type #1419, #1702
time: allows for model level StageActivation #1709
visualization: ChartModule can have dynamically named properties #1685
visualization: improved stop server to end visualizations #1646
experimental python front end option: integrated the initial prototype of the pure python front end option #1698, #1726

Improvements

update HexGrid and create HexSingleGrid and HexMultiGrid #1581
correct get_heading for toroidal space #1686
update slider to start at 1FPS #1674
update links to examples repo due to creation of mesa_examples #1636, #1637
** CI Improvements**
- update Ruff #1724
- remove Pipfile and Pipfile.lock #1692
- enable Codespell in Jupyter #1695
- improve regex for better build #1669, #1671
- exclude notebooks form linter #1670
- updated pip for zsh #1644
- CLI quality of life improvements #1640
Docs Improvements
- update to PyData theme #1699
- remove .rst to create simpler build #1363, #1624
- use seaborn in tutorials #1718
- fix types and errors in docs #1624, #1705, #1706, #1720
- improve tutorials #1636, #1637, #1639, #1641, #1647, #1648, #1650, #1656, #1658, #1659, #1695, #1697,
- add nbsphinx to adv_tutorial #1694
- replace const chart for var chart in advanced tutorial #1679
update LICENSE to 2023 #1683

Scientific Software - Peer-reviewed - Python
Published by rht over 2 years ago

Mesa 3 - v1.2.0 Taylor

Taylor release v1.2.0.

Scientific Software - Peer-reviewed - Python
Published by rht almost 3 years ago

Mesa 3 - v1.1.1

This release fixes https://github.com/projectmesa/mesa/issues/1461 where custom user-specified portrayal images don't load in the visualization server.

Full Changelog: https://github.com/projectmesa/mesa/compare/v1.1.0...v1.1.1

Scientific Software - Peer-reviewed - Python
Published by rht about 3 years ago

Recent Releases of Mesa 3

Mesa 3 - v3.2.0

Highlights

Stabilization of Discrete Space

Enhanced Visualization Experience

Restructured and updated tutorial

Introducing Meta-Agents

Other improvements

What's Changed

🎉 New features added

New Contributors

Mesa 3 - v3.1.5

Highlights

What's Changed

📜 Documentation improvements

Mesa 3 - v3.1.4

Highlights

What's Changed

🛠 Enhancements made

New Contributors

Mesa 3 - v3.1.3

Highlights

New Continuous Space Features

Create a 2D continuous space

Create and position an agent

Move agent using vector arithmetic

Get neighbors within radius

Find k nearest neighbors

What's Changed

🧪 Experimental features

New Contributors

Mesa 3 - v3.1.2

Highlights

What's Changed

🔍 Examples updated

New Contributors

Mesa 3 - v3.1.1

Highlights

What's Changed

🎉 New features added

New Contributors

Mesa 3 - v3.1.0

Highlights

What's Changed

🧪 Experimental features

New Contributors

Mesa 3 - v3.0.3

Highlights

What's Changed

🧪 Experimental features

Mesa 3 -

Highlighst

What's Changed

🐛 Bugs fixed

Mesa 3 - v3.0.1

Highlights

What's Changed

🧪 Experimental features

New Contributors

Mesa 3 - v3.0.0

Highlights

Streamlined agent management

Find agents meeting specific criteria

Group and analyze agents

Activate agents in different patterns

Modern Visualization with SolaraViz

Enhanced data collection

Experimental features

Breaking changes

Old

New

Old (RandomActivation)

New

Old (SimultaneousActivation)

New

Getting Started

What's Changed

⚠️ Breaking changes

New Contributors

Mesa 3 - Mesa 3.0 Release Candidate