title
Release History

2.2.2 (2024-01-22)

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

2.2.1 (2024-01-16)

Highlights

After the huge 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.

What's Changed

🧪 Experimental features

jupyter_viz: Implement multiline plot by @rht in projectmesa#1941

🛠 Enhancements made

make mesa runable without some dependencies by @Corvince in projectmesa#1950
Improve performance of AgentSet and iter_cell_list_contents by @Corvince in projectmesa#1964

🐛 Bugs fixed

Bugfix in agentset to handle addition and removal correctly by @quaquel in projectmesa#1960
Make RandomActivationByType.agents_by_type backward compatible by @quaquel in projectmesa#1965

📜 Documentation improvements

Refer to just Python instead of Python 3 by @rht in projectmesa#1957
intro tutorial: Analysing model reporters by @EwoutH in projectmesa#1955

🔧 Maintenance

Migrate from setuptools to hatch by @rht in projectmesa#1882
ci: Add tests for mesa-examples by @rht in projectmesa#1956
refactor: Move Matplotlib-specific Solara components to separate file by @rht in projectmesa#1943

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

2.2.0 (2024-01-09)

Highlights

The 2.2.0 release of the Mesa library introduces several updates and new features for managing and scheduling agents and modelling the environment, along with an experimental release policy aimed at enhancing development speed and community feedback. Below are key highlights of the new (experimental) features in this release. Mesa 2.2.0 supports Python 3.9+.

Despite the minor version number, this is one of our biggest releases yet.

Experimental feature policy (discussion #1909)

This release introduces an experimental feature policy aimed at accelerating development and gathering community feedback. Features like #1890, #1898, and #1916 are marked as experimental under this policy.

Policy overview:

Experimental features can be added or changed in any release, even patch releases.
They don’t need a diligent review for every change, allowing for quicker development cycles.
Community feedback is encouraged through discussion threads.

Native support for multiple Agent types (PR #1894)

This update introduces a agents variable to the Mesa Model class, offering a first step in supporting multiple agent types as first class citizens. Each Model is now initialized with an self.agents variable (an AgentSet) in which all the agents are tracked. You can now always ask which agents are in the model with model.agents. It's the foundation which will allow us to solve problems with scheduling, data collection and visualisation of multiple agent types in the future.

🧪 AgentSet class (PR #1916)

The new AgentSet class encapsulates and manages collections of agents, streamlining the process of selecting, sorting, and applying actions to groups of agents.

Key features:

Flexible and efficient agent management and manipulation.
Methods like select, shuffle, sort, and do for intuitive operations.

Example:

# Applying a method to each agent
model.agents.do('step')

# Filtering and shuffling agents
shuffled_agents = model.agents.select(lambda agent: agent.attribute > threshold).shuffle()

The AgentSet is an experimental feature. We would love feedback on it in #1919.

🧪 PropertyLayer and _PropertyGrid (PR #1898)

The introduction of PropertyLayer and the extension of SingleGrid and MultiGrid classes to support cell properties mark a significant enhancement in Mesa's environmental modeling capabilities. It allows to add different layers of variables to grids, that can be used to represent spatial environmental properties, such as elevation, pollution, flood levels or foliage.

Key features:

Efficient management of environmental properties like terrain types and resources.
Dynamic interaction between agents and their environment.
Fast modification and selection of cells based on one or multiple properties

Example:

from mesa.space import SingleGrid, PropertyLayer

grid = SingleGrid(10, 10, False)
property_layer = PropertyLayer("elevation", 10, 10, default_value=0)
grid.add_property_layer(property_layer)

# Modify multiple cells values
grid.properties["elevation"].modify_cells(np.multiply, 2)

# Select cells that have an elevation of at least 50
high_elevation_cells = grid.properties["elevation"].select_cells(condition=lambda x: x > 50)

The PropertyLayer is an experimental feature. We would love feedback on it in #1932.

🧪 DiscreteEventScheduler (PR #1890)

The DiscreteEventScheduler is an innovative addition to the Mesa time module, tailored for discrete event simulations. This scheduler advances simulations based on specific event timings rather than regular intervals, providing more flexibility in modeling complex systems.

Key Features:

Efficient handling of events scheduled for specific simulation times.
Randomized execution order for events scheduled at the same time.

The DiscreteEventScheduler is an experimental feature. We would love feedback on it in #1923.

What's Changed

🧪 Experimental features

Native support for multiple agent types by @EwoutH in projectmesa#1894
space: Implement PropertyLayer and _PropertyGrid by @EwoutH in projectmesa#1898
Add DiscreteEventScheduler by @EwoutH in projectmesa#1890

🎉 New features added

Introduce AgentSet class by @EwoutH in projectmesa#1916

🛠 Enhancements made

Reimplement schedulers to use AgentSet by @quaquel in projectmesa#1926
space: Let move_agent choose from multiple positions by @EwoutH in projectmesa#1920

🐛 Bugs fixed

Work around for initializing model._agent by @quaquel in projectmesa#1928
Honor disabled space drawer option when rendering in the browser by @rlskoeser in projectmesa#1907

📜 Documentation improvements

Document empties property by @EwoutH in projectmesa#1888
docs: Fix README.md inline code formatting by @rht in projectmesa#1887

🔧 Maintenance

ci: Speed up pip install by caching deps install output by @rht in projectmesa#1885
Create release.yml file for automatic release notes generation by @EwoutH in projectmesa#1925
Drop support for Python 3.8 by @rht in projectmesa#1756

New Contributors

@quaquel made their first contribution in projectmesa#1928

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

2.1.5 (2023-11-26)

This release has some critical fixes to JupyterViz/Solara frontend to prevent flickering and improve the display of the jupyter plots. It also has improvements to datacollection and the documentation.

Improvements

datacollection: check if model reporters is a partial function (#1872)

Docs and Tutorial

docs: convert README from .rst to .md (#1881)
docs: convert HISTORY from .rst to .md (#1873)
docs: enhance docstrings for scheduler classes in mesa.time (#1866)

CI and WorkFlows

ci: Remove redundant Ruff workflow from GitHub Actions (#1880)
Replace Black with ruff format (#1880)
Migrate setup from setup.py to pyproject.toml (#1870)

Solara/JupyterViz

fix: Do render_in_jupyter on Colab env (#1884)
Convert make_space into Solara component (#1877)
remove controls for dragging and resizing (#1878)
Improve ColorCard layout (#1876)
refactor: Define current_step as reactive (#1875)
fix: optimize controller and plots to fill screen in jupyter (#1868)
fix: ensure space and plot subcomponent are not rendered on step (#1867)

2.1.4 (2023-11-7)

This release updates mesa-viz-tornado dependency v0.1.3. This removes the external JavaScript templates and prevents 404 errors

bugfix: ensure mesa_viz_tornado>=0.1.3 #1862

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 mesa_viz_tornado>=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

2.1.2 (2023-09-23)

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 make_user_input 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 exclude_none_values #1813

2.1.1 (2023-08-02)

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

Changes:

: - Update intro_tutorial 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 -> get_heading() #1739

2.1.0 (2023-07-22) 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 (directly below this), as this contains the details about the breaking changes and other major changes that were part of Mesa 2.0 release.

Changes:

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

2.0.0 (2023-07-15) Wellton

Special notes

Mesa 2.0 includes:

: - an experimental pure python user interface/ visualization that is also jupyter compatible please see the visualization tutorial_ - an improved datacollector that allows collection by agent type - several breaking changes that provide significant improvements to Mesa.

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_neighbors()`

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.

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

1.2.1 (2023-03-18)

This release fixes projectmesa#1606, where mesa startproject doesn't work.

Changes:

fix: Include cookiecutter folders in install content #1611
Fix Ruff errors and pin Ruff version #1609
datacollector: Add warning when returning empty dataframe with no reporters defined #1614

1.2.0 (2023-03-09) Taylor

Special notes

New features:

Implement radius for NetworkGrid.get_neighbors #1564

Some highlights for the perf improvements:

Use getattr for attribute strings in model data collection #1590 this is a 2x speedup over the relevant line
Faster is_integer function for common cases #1597 is for 1.3x speedup for grid access (grid[x, y])
Refactor iter/get_cell_list_contents methods #1570 at least 1.3x speedup for iter/get_cell_list_contents
Evaluate empties set more lazily #1546 (comment) ~1.3x speedup for place_agent, remove_agent, and move_agent

Improvements

ci: Add testing on Python 3.11 #1519
Remove auto-update GH Actions for Pipfile.lock #1558

ruff

:   -   ruff: Add isort #1594
    -   ci: Replace flake8 with Ruff #1587
    -   ruff: Add more rules based on Zulip\'s config #1596

perf: faster is_integer function for common cases #1597
Remove _reporter_decorator #1591
Change index at DataFrame creation in get_agent_vars_dataframe #1586
Make Grid class private #1575
Make the internal grid and empties_built in Grid class private #1568
Simplify code in ContinuousSpace #1536
Improve docstrings of ContinuousSpace #1535
Simplify accept_tuple_argument decorator in space.py #1531
Enhance schedulers to support intra-step removal of agents #1523
perf: Refactor iter_cell_list_contents Performance #1527
Replace two loops with dictionary comprehension, list- with generator comprehension #1458
Make MultiGrid.place_agent faster #1508
Update space module-level docstring summary #1518
Update NetworkGrid.__init__ docstring #1514
Deprecate SingleGrid.position_agent #1512
Make swap_pos part of Grid instead of SingleGrid #1507
Refactor NetworkGrid docstrings and iter/get_cell_list_contents #1498
Hexgrid: use get_neighborhood in iter_neighbors #1504
Auto update year for copyright in docs #1503
Refactor Grid.move_to_empty #1482
Put "Mesa" instead of "it" in README #1490
Batchrunner: Remove unnecessary dict transformation, .keys() in len() #1460
Add Dependabot configuration for GitHub Actions update check #1480
Use list transformation only when shuffled is True #1478
Implement swap_pos #1474
Clean up DataCollector #1475

Fixes

Update resources in README #1605
Fix accident from projectmesa#1488 #1489
pre-commit autoupdate #1598, #1576, #1548, #1494
Fix docstring of DataCollector #1592
Update Pipfile.lock (dependencies) #1495 #1487

build(deps):

:   -   build(deps): bump codecov/codecov-action from 2 to 3
        dependencies Pull requests that update a dependency file
        #1486
    -   build(deps): bump actions/upload-artifact from 2 to 3
        dependencies Pull requests that update a dependency file
        #1485
    -   build(deps): bump peter-evans/create-pull-request from 3 to
        4 dependencies Pull requests that update a dependency file
        #1484
    -   build(deps): bump actions/setup-python from 3 to 4
        dependencies Pull requests that update a dependency file
        #1483

Establish reproducibility for NetworkGrid.get_neighbors when radius > 1 #1569
Format js code #1554
Add some missing const declarations #1549
fix tutorial url in examples #1538
Update cookiecutter to flat import style. #1525
Fix bug in Grid.get_neighborhood #1517
Revert changes of #1478 and #1456 #1516
Fix return types of some NetworkGrid methods #1505
Update year for copyright #1501
Add default_value function to NetworkGrid #1497
Remove extraneous spaces from docstrings in modules 2 #1496
Remove extraneous spaces from docstrings in modules #1493
SingleGrid: Remove extraneous attribute declaration (empties) #1491

1.1.1 (2022-10-21)

This release fixes projectmesa#1461 where custom user-specified portrayal images don't load in the visualization server.

1.1.0 (2022-10-10) Safford

Special notes

Perf: ContinuousSpace: speed-up add/remove agents #1376. This is a ~6x performance improvement for add/remove.
fix: time: Recompute agent_keys between stages #1391. This is a correctness fix for SimultaneousActivation and StagedActivation when agents are being removed during simulation.
ModularServer: Always set model.running = True on reset #1399. With this change, specifying self.running = True in your model __init__ is now optional. Mesa's visualization server will automatically sets it to True in the beginning of a simulation.
feat: Allow user-specified local dir to be served by Tornado #1435. This simplifies the usage of ModularServer in Mesa-Geo.
Allow batch_run to take arbitrary parameters #1413. With this change, you can finally use any arbitrary Python objects as batch_run parameters, where previously they are restricted to hashable objects only.
Prevent seed and random from being shared between instances #1439. With this fix, a model instance has their own isolated RNG.

Improvements

CI Updates

:   -   ci: Cancel previous obsolete runs #1378
    -   ci: update black to prevent click error #1382
    -   Add \"falsy\" to .codespellignore #1412
    -   Upgrade pre-commit CI (with pyupgrade and syntax checks)
        #1422

Tests

:   -   test: RandomActivationByType: Test adding agents with
        duplicate ID #1392

Dependency updates

:   -   Update Pipfile.lock (dependencies) #1398
    -   Update Pipfile.lock (dependencies) #1408
    -   Update Pipfile.lock (dependencies) #1434

Docs

:   -   docs: Add Tim Pope\'s guideline for proper Git commit msg
        #1379
    -   readme: Improve the pip install for Git repo instruction
        #1416
    -   Docs: Remove trailing whitespaces #1421
    -   Fixes #1423 - fixes build badge in docs #1424

Refactors

:   -   refactor: Apply pyupgrade \--py37-plus #1429
    -   refactor ModularServer (moving code into \_\_init\_\_) #1403

Perf: ContinuousSpace: speed-up add/remove agents #1376
Remove monospace formatting for hyperlinks #1388
ModularServer: Always set model.running = True on reset #1399
Allow batch_run to take arbitrary parameters #1413
ModularServer: Put new optional arg port last #1432
feat: Allow user-specified local dir to be served by Tornado #1435
Improve and measure speed of clamp function #1440

Fixes

Fix stray " in modular_template.html #1380
Fix zoom on network visualisation #1381
Fix broken monospace links #1387
fix: Ensure agent id is unique in RandomActivationByType.add #1386
fix: time: Recompute agent_keys between stages #1391
Fix batchrunner progress bar #1395
Fix stray " in visualisation dropdown labels #1409
space: Fix type error for Python < 3.9 #1430
Prevent seed and random from being shared between instances #1439

1.0.0 (2022-07-06) Quartzsite

Special notes

BREAKING: Rename mesa.visualizations.TextVisualization.TextElement to ASCIIElement
POTENTIALLY BREAKING: Default batch_run to 1 CPU #1300
Simplified namespace implements - see Improvements section.

Improvements

Implement simplified namespace

:   -   docs: simplified namespace tutorial update #1361
    -   examples: Convert shape_example, sugarscape_cg,
        virus_on_network, wolf_sheep to simple namespace #1339
    -   Convert hex_snowflake, pd_grid, schelling to simple
        namespace; \[BREAKING\] Remove class name collision #1333
    -   examples: Convert color_patches, conways_game_of_life,
        epstein_civil_violence, forest_fire to simple namespace
        #1331
    -   Examples: Convert boltzmann_wealth_model_network and chart
        to simple namespace #1322
    -   examples: Convert boid_flockers, boltzmann_wealth_model to
        simple namespace #1321
    -   examples: Convert bank_reserves to simple namespace #1317
    -   add batch_run to simple namespace #1316
    -   Implement simpler Mesa namespace #1294

mypy

:   -   mypy: Use \"\|\" operator instead of Union/Optional #1345
    -   mypy: Improve space.py annotation, part 2 #1219
    -   mypy: Improve annotations #1212

Userparam class updates

:   -   feat: Implement NumberInput UserParam class #1343

    -   feat: Implement StaticText UserParam #1342

    -   feat: Implement Choice UserParam class #1338

    -   feat: Implement Checkbox UserParam class #1332

    -

        feat: Implement Slider UserParam class #1272

        :   -   examples: Convert to using Slider UserParam class
                #1340

Front-end updates

:   -   frontend: Add alignment options to agent portrayals in
        CanvasGridVisualization #1349

    -   frontend: Update Bootstrap 4.6.1 -\> 5.1.3 #1325

    -   ChartModule.js: Use more semantic HTML element creation
        method #1319

    -   Issue #1232; Replaced usage of var to const/let in some
        files #1248

    -   \[Issue 1232\] Refactor NetworkModuleSigma PieChartModule
        TextModule JS #1246

    -   js: Update D3 from 4.13.0 to 7.4.3 #1270

    -   support package and local css includes #1283

    -   Upgrade to Bootstrap 4! #1282

    -   refactor: update var to const/let in InteractionHandler.js
        #1273

    -   Change remaining vendored JS dependencies to be downloaded
        during install #1268

    -   Download jQuery and D3 during install #1260

    -   CSS support for custom visualization element #1267

    -   style: prettify js files #1266

    -   refactor: Change var to const/let for remaining js files
        #1265

    -   Remove NetworkModule_sigma and its dependencies #1262

    -   js: Download bootstrap-slider during install #1257

    -   js deps: Move Bootstrap to be inside external folder #1236

    -   Apply prettier to NetworkModule_d3.js #1225

    -   js: Download Bootstrap on-the-fly during install instead
        #1220

    -   Install JS dependencies using Fanstatic #1195

    -

        JQuery updates

        :   -   examples: Remove all usage of jQuery #1356
            -   Remove jQuery dependency completely #1355
            -   refactor: frontend: Remove remaining usage of jQuery
                #1351
            -   refactor: frontend: Remove usage of jQuery for most
                of the JS code #1348
            -   refactor: frontend: Remove jQuery usage in
                CanvasHexModule.js & CanvasModule.js #1347
            -   refactor: frontend: Remove jQuery usage in
                BarChartModule.js #1326
            -   visualization: Specify tooltip without jQuery #1308

CI Updates

:   -   ci: Ensure wheel is install before pip install step #1312
    -   Fix contributing (increasing black version) #1303
    -   ci: Disable PyPy for now #1254
    -   CI: Update checkout, setup-python and cache actions to v3
        #1217
    -   CI: Split off codespell job, don\'t run build on doc changes
        #1170
    -   ci: Add 6 min timeout for the test jobs #1194
    -   CI: test flake: batch runner sometimes takes 6 hours then
        gets killed by GitHub Actions #1166
    -   ci: Enable cache for all Python versions 🇺🇦 #1177
    -   CI: Create Action to publish to PyPI on release #1169
    -   CI: Python 3.6 should be removed because it has reached EOL
        #1165
    -   Update Black formatting (no spaces for power operator) #1160
    -   Improve code quality with static analysis #1328
    -   CI test: Increase timeout to 10 minutes #1250

Dependency updates

:   -   build(deps): bump cookiecutter from 2.1.0 to 2.1.1
        dependencies #1360
    -   Update Pipfile.lock (dependencies) #1374, #1350, #1301,
        #1224, #1203, #1135 by github-actions bot
    -   Migrate D3 from v4 to v7 #1088

Other Improvements

:   -   feat: Implement auto-conversion of function to TextElement
        #1346
    -   Readme: Add Matrix badge and description #1164
    -   examples: Convert nodes to list when drawing random
        sample#1330
    -   examples: Use nicer color for bank_reserves #1324
    -   examples: Use nicer color for chart #1323
    -   model: Implement initialize_data_collector #1287
    -   CONTRIBUTING: Add instruction to enable git pull autorebase
        #1298
    -   Improve MANIFEST.in #1281
    -   refactor: Merge \_remove_agent into remove_agent #1245
    -   examples: Remove usage of internal method \_remove_agent
        #1241
    -   refactor: Make \_place_agent args consistent with
        place_agent #1240
    -   Redirect user to GH discussions for seeking help #1237
    -   setup.py: Update setup classifiers and add python_requires
        for Python\>=3.7 #1215
    -   The tutorial.rst doesn\'t mention that the Pandas DataFrame
        output can be in CSV #1148
    -   Deprecate neighbor_iter in favor of iter_neighbors #1184
    -   Add snippet about using numpy\'s random #1204
    -   docs: make windows multiprocessing code appear #1201
    -   Capitalize CSV whenever applicable #1200
    -   update intro tutorial for pandas and CSV and batch_run and
        windows #1196
    -   docker-compose.yml: Make it consistent with Dockerfile #1197
    -   Improve Dockerfile #1193
    -   update to include Matrix and GitHub discussion links #1179
    -   Update docs to remove old discussion forums #1171
    -   Add \"Grass\" curve to wolf_sheep example chart #1178
    -   feat: Implement random activation by type #1162

Fixes

Git tags out of sync with conda and PyPi (0.8.8 and 0.8.9 missing on git) #1076
fix: Remove mesa.visualization.Number #1352
CI: the "install dependencies" step is slow #1163

Readme related

:   -   readme: Clarify/Update Docker instruction #1222, #1214
    -   Readme: Fix links to docs #1205

Add mesa/visualization/templates/js/external to gitignore #1320
fix: sugarscape_cg: Use better way to check if a cell is occupied by SsAgent #1313
fix double multiply of iterations in singleprocess #1310
pre-commit: fix required python version, correct example commit messa... #1302
fix: Make bank_reserves batch_run example work #1293
Fixes #498. Replaces canvas_width with grid_rows to fill out color patches 3 - Accept easy task!!! #989
update pre-commit to include jupyter; fix warning #1190
fix: Grid.__getitem__: Handle Numpy integers #1181
fix: Make argument order in example models consistent #1176
issue template: Linkify discussions url #1239
batch_run: Do not iterate values when it is a single string #1289
examples: Clarify install instruction in wolf_sheep #1275
test: Disable batchrunnerMP (CI: test flake: batch runner sometimes takes 6 hours then gets killed by GitHub Actions #1166) #1256
examples: correcting comment in examples/pd_grid/pd_grid/agent.py #1247
space: Clarify the return object of get_cell_list_contents #1242
width and height were changed up #1149
fix typo in best-practices.rst #1368
fix: examples: Make space x, y order consistent #1366

0.9.0 (2022-01-31) Page

Improvements

Update number_processes and associated docs #1141
[PERF] Improve move_to_empty performance #1116
Adding logic to check whether there is agent data #1115
Convert all text strings to f-strings #1099
Format Python and Jupyter Notebook files with Black #1078
README: Add info on how to cite Mesa #1046
Re-Implementation of BatchRunner #924

CI Related

:   -   CI: Add workflow to update Pipfile.lock every month #1018
    -   CI: Lint typos with Codespell #1098
    -   CI: Only run Codecov on Ubuntu jobs and update to v2 #1083
    -   CI: Maintenance: Update to Python 3.10, split of lint jobs
        #1074

Dependency updates

:   -   Updates to Pipfile.lock (dependencies) #1114, #1086, #1080
    -   Update Pipfile to use Python 3.9 #1075
    -   Update Chart.js to 3.6.1 (v3) #1087
    -   Update Chart.js to version 2.9.4 #1084
    -   Pyupgrade 3.6: Update syntax with Python 3.6+ features #1105
    -   Bump urllib3 from 1.26.2 to 1.26.5 #1043
    -   Update packages.rst #1068

Docs

:   -   Update docs/README.md #1118
    -   Update number_processes and associated docs #1141
    -   Update section \'Batch Run\' of introductory tutorial #1119
    -   Readme: Add command to install specific branch #1111
    -   Docs: Add back some comments in space.py #1091
    -   Docs: Remove trailing white spaces #1106
    -   Update intro_tutorial.rst #1097, #1095
    -   Tweaking and improving the documentation #1072

Fixes

Rename i_steps -> data_collection_period and add docstring #1120
bank_reserves: Say that the commented out legacy code is for comparison #1110
Fix broken image on PyPI #1071

Docs

:   -   Fix numbering typos in docs/README.md #1117
    -   Readme: Fix command for installing custom branch on fork
        #1144
    -   Docs: space.py: Fix single case of neighbor spelled as
        neighbour #1090

0.8.9 (2020-05-24) Oro Valley

Note: Master branch was renamed to Main on 03/13/2021

Improvements

Master to Main change:

:   -   Docs/examples: Update links to use main instead of master as
        branch #1012
    -   CI: Run on pushed to main and release branches #1011

Github Actions

:   -   GitHub Actions: run black only on ubuntu 3.8 #996
    -   GA: Only run CI when pushed to master #974
    -   GA: Add pypy3 #972
    -   rename github action to \"build\", remove redundant flake8
        check #971
    -   GA: Run on Windows and macOS #970
    -   Add GitHub Action for continuous integration testing #966

[PERF] Add neighborhood cache to grids and improve iter_cell_list_contents #823
forest_fire: Remove unnecessary code #981
Migrate away from type comments #984
Update License #985
Public remove_agent function for NetworkGrid #1001
Date update to release #962
Advanced indexing of grid #820

Fixes

Correct spelling #999
Update Pipfile.lock #983
Fix order of variable_params in model and agent vars data frames #979
Fix asyncio on windows with python 3.6 #973

0.8.8 (2020-11-27) Nogales

Note: This is the last version to support Python 3.5.

Improvements

Added pre-commit to automatically maintain a standard formatting with black #732

Fixes

MultiGrid: Set to using list for cell content #783

Docs

:   -   Fixed broken link to templates list in advanced tutorial.
        #833
    -   Fixed image links in rst #838
    -   Cleaned html to attempt correct build #839
    -   Fixed links on Boltzmann model #843
    -   Documentation update - batchrunner & data collector #870
    -   Deleted readthedocs.yml #946
    -   Doc builds #837, #840, #844, #941, #942

Fixed bulleted list in contribution read me #836
Updated test_examples.py, changed unused generator expression to actually run the models. #829
Fixed #827 issue (example Epstein Civil Violence Jupyter Notebook typos) #828
Eliminated Ipython3 references #841
Fixed cookie cutter Fixes #850. #853
Removed relative imports -- fix #855. #863
Updated pytest requirement to fix issues on travis #864
Made linux compatible - travis #886
Fixed python 3.5 fails, boid failure #889, #898
Travis: Removed python 3.5 #899
Fixed example testing issues close multiprocess pools #890
Used ordered dict to make compatible with python 3.5 #892
Increased number of test to fix codecov patch #916
Fixed for #919, adding an exception for duplicate ids. #920

Batchrunner

:   -   Batch runner redux #917
    -   Fixed empty/None `variable_parameters` argument to
        BatchRunner (#861) #862
    -   Added ordereddict to BatchrunerMP for python 3.5 #893
    -   Fixed python 3.5 fails bathrunnerMP (multiple tries) #897,
        #896, #895
    -   Batchrunner_redux fixes #928

Fixed variables names, mp function locations, datacollector #933
ModularServer updated: Fix EventLoop and changes to default port #936
Ran black 20.8b1, which formats docstrings #951

0.8.7 (2020-05-05) Mammoth

Improvements

Enable BatchRunner to run specified set of parameter combinations #651 (#607)
Restructured runcontrol.js #661
Add pipenv support for mesa #678
Increase test coverage and change to codecov #692
Updates Travis to explicitly set the dist to be Xenial #699
time: Remove resolved TODO on random seed of random scheduler #708
hex_snowflake: Update description to be more informative #712
Added Coverall to Codecov in Contributing file #734
Makes opening the browser optional when launching the server #755 #754
NetworkGrid: Update to networkx 2.4 API #763
Apply black to mesa/ directory #775
Updated travis to 3.8 and updated gitignore #777
Add information (to docstring) on image as agent portrayal shape #791
Change grid empties from list to set #649 (improves speed)

Adding mypy annotation

:   -   space: Add type annotation to Grid class #779
    -   add Mypy annotation to time, agent, and model #792
    -   space: Add mypy annotation to the remaining
        methods/functions #796

Docs related

:   -   Bulk merge of docs from \'docs\' to \'master\' #684

    -

        Created useful snippets code section in the docs #668 #669

        :   -   Updating index.rst #672
            -   Clarify runserver snippet in index.rst #682

    -   Add documentation for feature (pipenv) added in #678 #683

    -

        Add docs for BatchRunner to support Variable and Fixed Parameter Contribution #679 #683

        :   -   Resources #651 in docs branch #691. This preps for
                #683 to be merged.

    -   intro tutorial: Clarify a function that is not defined in
        the class #705

    -   Updates formatting the readme Docs markdown #737

Examples related

:   -   Schelling: Separate text-only viz into run_ascii.py #706
    -   examples/Readme.md: Update description to be consistent with
        the folder names #707

Fixes

Fixes link to update code coverage module - Updates Removing last link to coveralls and replacing to codecoverage #748
Fixes D3 Network Visualization to update (rather than overwrite) #765 #767
Fix parameter order in initializing SingleGrid object #770 #769
Updating pipenv link #773
Fixed pip install from github by specifying egg #802

Compatibility fixes

:   -   Fixes VisualizationServer to be compatible with recent
        versions of Tornado #655
    -   Fixes #749 networkx incompatibility #750

Fixing typos

:   -   Fixes documentation typos in example code #695 #696
    -   Fixes typo in ModularServer\'s last parameter #711
    -   Fixed typo in BarChartModule line 100 #747
    -   Fix typo in documentation #809

Doc fixes (not relating to typos)

:   -   Update tutorial to point to correct repo location #671 #670
    -   Updating sphinx and reverting issues #674 #675 #677 #681
    -   Fixes code blocks that weren\'t showing up in the tutorial
        #686
    -   Remove figure from advanced tutorial showing the empty
        visualization #729
    -   Removes git clone from tutorial - Update intro_tutorial.rst
        #730
    -   Fixes citation links in docs tutorial section #736
    -   Fix histogram in advanced tutorial #794 #610
    -   Fixes Advanced Tutorial #elements #804 #803

Fixes to examples

:   -   Fixing test_random_walk bug - wolf sheep. #821
    -   Fixes shape_example server launch #762 #756
    -   Fixing broken table in pd_grid example #824

0.8.6 (2019-05-02) Lake Havasu City

Improvements

add docker-compose + Dockerfile support #593
install: Remove jupyter requirement #614
Add Bar and Pie Chart visualization #594 #490
Make models pickleable #582

Fixes

Year update. Happy New Year! #613
Fixed problem with grid and chart visualization javascript #612 #615
removed extra" .random" on line 178. #654
updated requirement for networkx #644 #646
Fix VisualizationServer to be compatible with recent versions of Tornado #655

0.8.5 (2018-11-26) Kearny

Improvements

Added mouse interactionHandler to close #457, fixed hexgrid drawLines #465
Run examples as part of the tests #529, #564
Add a github issue template. #560
Changes nose to pytest #561
Update and clean up cookiecutter layout #563
Updating setup to move requirements to setup.py. #566
Fixes #570 removed and updated stale comments in space.py #571
Adding model random number generator with __new__ #572
Faster agent attribute collection #576
Update install command to be edible #578
Adding read the docs yml. #579
agents can be removed and added during Scheduler.step() #584
Adding a description to bank_reserves. #587
F8 cleanup #600

Fixes

Fixes #543 (User Settable Parameters fail to work for non-string datatype #543) #544
Adding missing requirements files to examples. #550
Fixes issue #548, flockers visualization not showing up #548
updated BatchRunner (throwing error when passing in agent reporters) #556
Removing version numbers and fixing flake8 issues. #562
Fix issue #548 (Flockers visualization is not working) #566
Fixes code formatting in readmes. #577
Batchrunner.fix (BatchRunner's "variable parameters" is not strictly optional) #596

0.8.4 (2018-06-17) Jerome

Improvements

Mesa Packages docs created (#464, #480, #484, #503, #504)
Change size and tooltip text of nodes in D3 network visualization #468
Multiprocessing BatchRunner with pathos #506
Schedule.agent.dict - Implement tracking the agents in the scheduler via OrderedDict #510
Use click and add mesa run #522
Add a code of conduct #530

Fixes

iter_neighborhood() now gives correct neighborhoods for both von Neumann and Moore #459
fix typo #461
Flockers update & subsequent "F" versus "f" fix on Unix/Mac - #477, #518, #525, #500
Fixing date on release. #453
Batchrunner fixes: properly initialize models with correct parameters during subsequent runs. #486
Tornado Version Bug Fixes (upgrading #489, downgrading #497, adding to setup.py #527)
fix minor flake8 issues #519
align required dependencies between setup.py and requirements.txt #523, #528, #535
Fixes #499 grid size issue. #539

0.8.3 (2018-01-14) Hayden

Improvements

Datacollector fix #445
A first network grid model with visualization, using NetworkX and sigma.js #388
Cache pip packages for Travis setup #427
Remove localhost hardcoding + allow secure sockets #421
Update Chart.js to version 2.7.1 #401
Bank reserves example #432
Extended Grid to support hexagonal grids #409

Fixes

Faster ContinuousSpace neighbor search #439
Updating license year to 2018 #450
Updating language on license in contributing file #446
Updating license year to 2018 #450
Removed mutable defaults from DataCollector constructor #434
[BUGFIX] Torus adjustment in Grid class #429
Batchrunfixedparameters #423
[BUGFIX] Fix sidebar visibility in Edge #436
Updating Travis svg to target #master, not branches. #343
Email list language updates and link updates #399
Fix math problems in flockers; use numpy in space #378
Only start tornado ioloop if necessary #339
ContinuousSpace: Fix get_distance calculation on toroidal boundary condition #430

0.8.2 (2017-11-01) Gila Bend

Improvements

Split parameter_values into fixed & variable parameters in batchrunner #393

Fixes

Updating License year to 2017 -- very minor update #391
Flockers: fix param naming #398
Remove unused class parameters. #400
[hotfix!] Disable e2e viz test for now. #414

Fixing bug in release process. \[6a8ecb6\]

:   -   See <https://github.com/pypa/pypi-legacy/issues/670>.

0.8.1 (2017-07-03) Flagstaff (PyCon Sprints & then some)

Improvements

Bootstrap UI starter #383
Add Sugarscape Constant Growback example #385
Add best-practices document and describe models. #371

Refactored & model standards related:

:   -   Prisoner\'s Dilemma refactor to meet new model standard
        format. #377
    -   refactored boltzmann wealth model to new layout #376
    -   Update tutorial to follow new model standards #370
    -   Moving wolf sheep pngs to sub-folder for better organization
        #372
    -   Add best-practices document and describe models. #371

Modified loop over agents in schedule step method #356
Added function to use local images as shapes in GridDraw #355

Fixes

Fix math problems in flockers; use numpy in space #378
Seed both global random number generators #373, #368
Dictionary parameters fix #309
Downgrade setuptools to fix #353
Minor forest fire fix #338, #346
Allow fixed seed for replication #107
Fix tutorial and example readme for port change 8b57aa

0.8.0 (2017-01-29) - Edgar

Improvements

Updating contribution file to prevent future travis breaks #336
Updating Travis svg to target #master, not branches. #343
implement "end" message in visualization #346
Move empty-cell functions to baseclass Grid #349

Fixes

Only start tornado ioloop if necessary #339
fix boundaries of ContinousSpace #345

0.7.8.1 (2016-11-02) Duncan

Improvements

Fixes #324 -- renames all examples to be the pythonic format of naming #328
Changing to port 8521, fixes #320. #321
Opens a browser window when launching the server #323
Ticket #314 - added progress bar to BatchRunner #316
Auto update year for copyright. #329

Fixes

Minor bug fixes - Update ForestFire example notebook to new API, and rename Basic to Shape Example. #318
On-demand model stepping rather than an endless buffer #310
Updating contribution to prevent future travis breaks #330

0.7.7 (2016-08-18)

Improvements

Fixes - variable name heading0/1 in ArrowHead shape is not intuitive. #295 #301
Fixes - ArrowHead shape is not reflecting in the docs of api #300 #301
Fixes - Documentation is not reflecting latest changes wrt width-height argument order in Grid() #296 #301

0.7.6 (2016-08-13)

Theme: Scipy Sprints 2016 ( '-')人(ﾟ_ﾟ ) & Then some.

Feature adds

Add new shapes & direction indication in CanvasGrid #285
Provides support for text overlay on Circle and Rectangle shapes. #265

Improvements

Fixes Parameters of CanvasGrid(): row, col, height, width inverted #285
Fixes 'coordinates on grid are used inconsistently throughout the code' #285
Moves Agent and Model class outside of __init__.py #285
Minor pep updates to boltzmann. #269
Fix link to intro tutorial. #267
Updating template text visualization/ModularVisualization.md #273
Update intro_notebook and documents to include self.running = True in MoneyModel #275
Update .rst file location to make sure ReadTheDocs works correctly #276
Remove Mock code causing recursion and preventing build of docs. #281
MultiGrid docstring missing methods #282
No Docstring for model.grid.get_cell_list_contents #282
Refactor forest fire example #223 #288
Updating kernel version on forest fire model. #290
Making examples pep complaint. fixes #270 #291
Fixed pep8 examples and #292 #294
Fixes #283 - Fixes formatting on viz readme #299
Have Agent use self.model instead of passing it around #297

0.7.5 (2016-06-20)

Pre-sprints

Update of tutorial files and docs #176, #172
Adds np.int64() functions around some variables to get rid error caused by numpy update #188
Made examples Readme.md more readable #189

From PyCon Sprints

Updating model example readmes #207
Added nose to requirements #208
Updated link on style google style guide #209
Reset visualization when websocket connection is opened #210
Remove unused scipy dependency #211
Introduce a requirements.txt for the tutorial. #212
Remove references to running in tutorial #213
Simplify travis.yml; add python versions #215
Update Flocker Readme.md #216
Syntax error in .rst was swallowing a code block #217
Fixup HistogramModule in the tutorial. #218
add more test coverage to time #221
add a requirements.txt for WolfSheep. #222
add a requirements.txt for Schelling. #224
Refactor color patches example #227
Ignored _build sphinx docs still in repo #228
Intro Tut completely in ipynb #230
pass optional port parameter to ModularServer.launch #231
open vis immediately when running color patches #232
Adds .DS_store to .gitignore #237
Documentation Update #240
Small fix for reading links #241
Test batchrunner #243
clean up TextVisualization #245
Documentation Update #250
Update Game of Life example to new format #253
Update Flockers example to new format #254
Update Epstein model to new layout #255
Subclassing object is unnecessary in Python 3 #258

Post PyCon Sprints

Adds a copy of jquery directly into the code. #261

0.7.0 (2016-03-06)

#184 Adding terminal echo for server launch to signal person running the model
#183 Adding Conway's Game of Life simulation to the examples.

0.6.9 (2016-02-16)

#170 Adding multi-stage activation
#169 Wolf-Sheep Cleanup
Updates requirements to latest libraries

0.6.7 (2015-07-11)

Improvements

Allow cell_list_content methods in Grids to accept single tuples in addition to lists

0.6.6 (2015-07-11)

Theme: Scipy Sprints ( '-')人(ﾟ_ﾟ )

Improvements

Standardizes the arguments passed to spatial functions to only tuples, not separate x and y coordinates. (Breaks backwards compatibility)

0.6.5.1 (2015-07-11) ++++++++++++++++++

Theme: Scipy Sprints ( '-')人(ﾟ_ﾟ )

Improvements

Adding version, license, copyright, title to __init__.py
Auto updating version in setup.py

Fixes

Updating MANIFEST.in to include visualization templates that were missing.

0.6.5 (2015-07-11)

Theme: Scipy Sprints ( '-')人(ﾟ_ﾟ )

Edits

Additions to tutorial doc
Minor edits to README & Intro
Minor edits / clean up to setup.py
Removing .ipynb_checkpoints
Removing out-of-date planning documentation.

Fixes

Use setuptools' find_packages function to get the list of packages to install, fixes #141

Improvements

Use package_data for include the web files
Use a MANIFEST.in file to include the LICENSE file in source distributions
Using conda on Travis allows much faster builds and test runs

0.6.2 (2015-07-09)

Improvement: Adding continuous space.
Improvement: Adding a simultaneous activation scheduler.

New models:

:   -   Flockers
    -   Spatial Demographic Prisoner\'s Dilemma (PD_Grid)

0.6.1 (2015-06-27)

Fixes: Order of operations reversed: agent is removed first and then it is placed.
Improvement: LICENSE_ was updates from MIT to Apache 2.0.

0.6.0 (2015-06-21)

Improvement: Add modular server feature, which breaks up a model into a .py file and a .js file. This breaks backwards compatibility.

Pre 0.6.0

Code that is pre-0.6.0 is very unstable.

Our initial release was 0.5.0 (2014-11).

It included code for placing agents on a grid; a data collector and batch runner; and a front-end visualization using HTML 5 and JavaScript.

General

Objects create -- Agent, Time, Space
Project moved to Python 3
Tornado server setup

Front-end

Front-end grid implemented
ASCII visualization implemented

Examples models

Forest Fire
Schelling
Wolf-Sheep Predation

0.1.0 (2014-09-19)

A conversation
Birth

Files

HISTORY.md

Latest commit

History

HISTORY.md

File metadata and controls

2.2.2 (2024-01-22)

Highlights

What's Changed

🐛 Bugs fixed

2.2.1 (2024-01-16)

Highlights

What's Changed

🧪 Experimental features

🛠 Enhancements made

🐛 Bugs fixed

📜 Documentation improvements

🔧 Maintenance

2.2.0 (2024-01-09)

Highlights

Experimental feature policy (discussion #1909)

Native support for multiple Agent types (PR #1894)

🧪 AgentSet class (PR #1916)

🧪 PropertyLayer and _PropertyGrid (PR #1898)

🧪 DiscreteEventScheduler (PR #1890)

What's Changed

🧪 Experimental features

🎉 New features added

🛠 Enhancements made

🐛 Bugs fixed

📜 Documentation improvements

🔧 Maintenance

New Contributors

2.1.5 (2023-11-26)

2.1.4 (2023-11-7)

2.1.3 (2023-11-5)

2.1.2 (2023-09-23)

2.1.1 (2023-08-02)

2.1.0 (2023-07-22) Youngtown

2.0.0 (2023-07-15) Wellton

1.2.1 (2023-03-18)

1.2.0 (2023-03-09) Taylor

1.1.1 (2022-10-21)

1.1.0 (2022-10-10) Safford

1.0.0 (2022-07-06) Quartzsite

0.9.0 (2022-01-31) Page

0.8.9 (2020-05-24) Oro Valley

0.8.8 (2020-11-27) Nogales

0.8.7 (2020-05-05) Mammoth

0.8.6 (2019-05-02) Lake Havasu City

0.8.5 (2018-11-26) Kearny

0.8.4 (2018-06-17) Jerome

0.8.3 (2018-01-14) Hayden

0.8.2 (2017-11-01) Gila Bend

0.8.1 (2017-07-03) Flagstaff (PyCon Sprints & then some)

0.8.0 (2017-01-29) - Edgar

0.7.8.1 (2016-11-02) Duncan

0.7.7 (2016-08-18)

0.7.6 (2016-08-13)

0.7.5 (2016-06-20)

0.7.0 (2016-03-06)

0.6.9 (2016-02-16)

0.6.7 (2015-07-11)

0.6.6 (2015-07-11)

0.6.5 (2015-07-11)

0.6.2 (2015-07-09)

0.6.1 (2015-06-27)

0.6.0 (2015-06-21)

Pre 0.6.0