3.99: Harmonize Solvers

[guyer]

This release harmonizes the sparse solvers:

• Uses consistent interpretation of convergence criteria.
• Improves efficiency at building matrices.
• Supports more preconditioners.
• Logs solver status and performance.
• Greatly expands documentation of the configuration and performance of the supported solvers.
• Changes default tolerance to $10^{-5}$. This is adequate for most problems.
• Removes "pyamg" from FIPY_SOLVERS and --pyamg from the command-line flags. PyAMG is implemented as a preconditioner for SciPy, not as a solver suite in its own right.

What's Changed

• build(nix): update to using latest Nix master version by @wd15 in build(nix): update to using latest Nix master version #1061
• Debug environment.yml installation by @guyer in Debug environment.yml installation #1064
• Prevent setuptools 72.x by @guyer in Prevent setuptools 72.x #1067
• Fix representation of dotted variables (and other method calls) by @guyer in Fix representation of dotted variables (and other method calls) #1074
• Handle exporting anonymous conda environment by @guyer in Handle exporting anonymous conda environment #1082
• Update byte-code for Python 3.13 by @guyer in Update byte-code for Python 3.13 #1095
• Generate root .rst files with sphinx_readme (README files viewed on GitHub.com render poorly #1104) by @obscurerichard in Generate root .rst files with sphinx_readme (#1104) #1105
• Passing ax parameter explicitly to colorbar - fix issue Recent version of matplotlib won't plot with colorbar #1087 by @cgadal in Passing ax parameter explicitly to colorbar - fix issue #1087 #1088
• issue1002-Setting nx, ny, nz to non-positive integer should generate an error by @sridhar-mani in issue1002-Setting nx, ny, nz to non-positive integer should generate an error #1083
• Resolve issues introduced by PETSc 3.23.0 by @guyer in Resolve issues introduced by PETSc 3.23.0 #1116
• Patch sphinx-readme by @guyer in Patch sphinx-readme #1125
• Fix conda timeout on Azure CI by @guyer in Fix conda timeout on Azure CI #1129
• Improve URL check implementation by @arpitjain099 in Improve URL check implementation #1130
• Link to proper CI for documentation by @guyer in Link to proper CI for documentation #1134
• Deprecate fipy.steppers in favor of steppyngstounes by @guyer in Deprecate fipy.steppers in favor of steppyngstounes #777
• Harmonize solvers by @guyer in Harmonize solvers #1030
• Reorganize Table of Contents by @guyer in Reorganize Table of Contents #1143

New Contributors

• @obscurerichard made their first contribution in Generate root .rst files with sphinx_readme (#1104) #1105
• @cgadal made their first contribution in Passing ax parameter explicitly to colorbar - fix issue #1087 #1088
• @sridhar-mani made their first contribution in issue1002-Setting nx, ny, nz to non-positive integer should generate an error #1083
• @arpitjain099 made their first contribution in Improve URL check implementation #1130

Curated Changelog: https://github.com/usnistgov/fipy/blob/3.99/CHANGELOG.rst

Full Changelog: 3.4.5...3.99

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This discussion was created from the release 3.99: Harmonize Solvers.

[guyer]

FiPy 3.99 is available for legacy codes that need Pysparse or Python 2.7. Be aware that neither have been supported in years.

🛑 FiPy 3.99 will receive no feature upgrades and will get bug fixes only under the most extreme circumstances. Upgrading to FiPy 4.0 is highly recommended. 🛑