v2.3.0

[EwoutH]

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 Add cell-centric discrete spaces (experimental) #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 support for discrete event scheduling #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 Add cell-centric discrete spaces (experimental) #1994

🎉 New features added

• Add performance benchmarking scripts by @EwoutH in Add performance benchmarking scripts #1979
• feat: Implement Slider class for JupyterViz by @rht in feat: Implement Slider class for JupyterViz #1972
• Stabilize AgentSet by @EwoutH in Stabilize AgentSet #2065
• Support discrete event scheduling by @quaquel in support for discrete event scheduling #2066

🛠 Enhancements made

• JupyterViz: Automatically deduce display name from model class by @rht in JupyterViz: Automatically deduce display name from model class #1975
• Add radius argument to NetworkGrid.get_neighbors() by @EwoutH in Add radius argument to NetworkGrid.get_neighbors() #1973
• Speedup of Agentset.shuffle by @quaquel in Speedup of Agentset.shuffle #2010
• feat: Let mesa runserver detect server.py as fallback by @rht in feat: Let mesa runserver detect server.py as fallback #2015
• JupyterViz: {Convert make_plot & prepare ColorCard} to become Solara component by @rht in JupyterViz: {Convert make_plot & prepare ColorCard} to become Solara component #2020
• new feature: AgentSet.get can retrieve one or more then one attribute by @quaquel in new feature: AgentSet.get can retrieve one or more then one attribute #2044
• Update CODE_OF_CONDUCT.md to version 2+ of contrib covenant by @jackiekazil in Update CODE_OF_CONDUCT.md to version 2+ of contrib convenant #2052
• Improve flocking benchmark by @coderbeta1 in Improve flocking benchmark  #2054
• Remove JupyterViz Altair marker overlap for huge grid size by @rht in Remove JupyterViz Altair marker overlap for huge grid size #2062
• Add tooltip option to Altair chart by @FoFFolo in Add tooltip option to Altair chart #2082
• feat: Display model seed & allow user to specify it in JupyterViz by @rht in feat: Display model seed & allow user to specify it in JupyterViz #2069
• warn if placing already placed agent by @puer-robustus in warn if placing already placed agent #2083

🐛 Bugs fixed

• fix: Apply default value to slider by @rht in fix: Apply default value to slider #2016
• fix: Initialize model _steps and _time during new by @rht in fix: Initialize model _steps and _time during __new__ #2026
• fix: Use model.schedule only when it is not None by @rht in fix: Use model.schedule only when it is not None #2050
• fix: Remove JupyterViz grid marker overlap for huge grid size by @rht in fix: Remove JupyterViz grid marker overlap for huge grid size #2049
• Make agent move to actual random closest position by @EwoutH in Make agent move to actual random closest position #2119

📜 Documentation improvements

• Improve readability of badges by @rht in Improve readability of badges #2009
• More pythonic implementation of wolf sheep by @quaquel in More pythonic implementation of wolf sheep #2011
• Adding super().init() to MoneyModel tutorial by @sw23 in Adding super().__init__() to MoneyModel tutorial #2025
• docs: Convert howto.rst -> howto.md via rst2myst by @rht in docs: Convert howto.rst -> howto.md via rst2myst #2033
• docs: Convert best-practices,overview,packages,mesa,index to .md via rst2myst by @rht in docs: Convert best-practices,overview,packages,mesa,index to .md via rst2myst #2034
• docs: Convert api/.rst -> api/.md via rst2myst by @rht in docs: Convert api/*.rst -> api/*.md via rst2myst #2035
• docs: Rewrite howto.md using ChatGPT for clarity and conciseness by @rht in docs: Rewrite howto.md using ChatGPT for clarity and conciseness #2037
• docs: Corrected Contributing Guide Link to Ensure Accessibility by @sahusiddharth in docs: Corrected Contributing Guide Link to Ensure Accessibility #2057
• Rename links to internal .rst files to .md by @rht in Rename links to internal .rst files to .md #2058
• docs: improve introductory tutorial by @puer-robustus in docs: improve introductory tutorial #2087

🔧 Maintenance

• Quality of Life: Make codecov less meticulous by @Corvince in Quality of Life: Make codecov less meticulous #1966
• Add CI workflow for performance benchmarks by @EwoutH in Add CI workflow for performance benchmarks #1983
• tests: Resolve warnings by defining PropertyLayer dtypes by @EwoutH in tests: Resolve warnings by defining PropertyLayer dtypes #1987
• benchmarks.yml: Fix PR branch checkout when triggered by comment by @EwoutH in benchmarks.yml: Fix PR branch checkout when triggered by comment #1998
• Quality of life: automatically fix ruff errors by @Corvince in Quality of life: automatically fix ruff errors #2004
• benchmarks.yml: Run on addition of label instead of comment by @EwoutH in benchmarks.yml: Run on addition of label instead of comment #2002
• ci: Move codespell to pre-commit by @rht in ci: Move codespell to pre-commit #2040
• Schelling by @coderbeta1 in Schelling #2053
• Move ruff lint settings into dedicated section by @Corvince in Move ruff lint settings into dedicated section #2073
• ci: Use uv pip for faster build by @rht in ci: Use uv pip for faster build #2038
• test: Remove place_agent duplicate warnings by @rht in test: Remove place_agent duplicate warnings #2086

Other changes

• Minor edits to benchmarking code by @quaquel in Minor edits to benchmarking code #1985
• build(deps): bump codecov/codecov-action from 3 to 4 by @dependabot in build(deps): bump codecov/codecov-action from 3 to 4 #2030
• [pre-commit.ci] pre-commit autoupdate by @pre-commit-ci in [pre-commit.ci] pre-commit autoupdate #2029
• tests: Speed up test_batch_run by @rht in tests: Speed up test_batch_run #2039
• Update benchmarks.yml by @Corvince in Update benchmarks.yml #2043
• docs: Convert visualization .rst -> .md via rst2myst by @rht in docs: Convert visualization .rst -> .md via rst2myst #2036
• docs: Convert CONTRIBUTING .rst -> .md via rst2myst by @rht in docs: Convert CONTRIBUTING .rst -> .md via rst2myst #2041
• Correct wolf energy gained from eating sheep by @JackAtOmenApps in Correct wolf energy gained from eating sheep #2048
• feat: Implement Altair version of grid visualization by @rht in feat: Implement Altair version of grid visualization #1991

New Contributors

• @sw23 made their first contribution in Adding super().__init__() to MoneyModel tutorial #2025
• @JackAtOmenApps made their first contribution in Correct wolf energy gained from eating sheep #2048
• @coderbeta1 made their first contribution in Improve flocking benchmark  #2054
• @sahusiddharth made their first contribution in docs: Corrected Contributing Guide Link to Ensure Accessibility #2057
• @FoFFolo made their first contribution in Add tooltip option to Altair chart #2082
• @puer-robustus made their first contribution in warn if placing already placed agent #2083

Full Changelog: v2.2.4...2.3.0

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This discussion was created from the release v2.3.0.