Version 1.4.0

• Dropped support for Python 3.8.
• Added support for Python 3.13.
• Added explicit dependency on setuptools.
• ConstraintCollocator raises an error if all equations of motion
  are algebraic, i.e. none are differential equations.
• plot_constraint_violations() now returns a variable number of
  subplot rows depending on the number of instance constraints. This
  makes the plot readable with large numbers of instance constraints.
• Internal common sub expression replacement symbols are now assumed
  to be real.
• Improvements to docstrings of Problem.solve().
• Added Problem.parse_free() to simplify use of the parse_free()
  function.
• Added attribute descriptions to ConstraintCollocator docstring.
• Support for single first order differential equation instead of
  limiting to two first order (i.e. only second order systems).
• Enabled math constants on Windows to support sympy.pi, for
  example.
• Made SciPy an optional dependency (was required).
• Fixed bug from backwards incompatible change in Python 3.13 for
  docstring indentation.
• Fixed bug where Problem.plot_ methods did not return anything.
• Fixed bug in trajectory plots so that the input trajectories are
  labeled with known, unknown, or both types of inputs.
• Made all ConstraintCollocator attributes properties with no setter
  methods, i.e. everything must be passed into the constructor to
  properly construct the object.
• Separated examples into beginner, intermediate, and advanced groups.
• Added MathJaxRepr for printing SymPy expressions in the example
  gallery.
• Use MathJax v2 in the documentation so that long expressions will
  line wrap.
• Examples added:
  • Ball rolling on spinning disc
  • Car moving around pylons
  • Car parking into a garage
  • Crane moving a load
  • Delay equation (inequality constraints example)
  • Human gait
  • Mississippi steamboat
  • Non-contiguous parameter identification
  • ODE vs DAE comparison
  • Particle moving through a helical tube
  • Single EoM & hypersensitive control
  • Sit-to-stand
  • Standing balance control identification

What's Changed

• Subexpression replacements in the Jacobian should be real. by @moorepants in #216
• Plot constraint violations by @Peter230655 in #218
• Added a example: crane moving a load by @Peter230655 in #197
• Handle variable h by @Peter230655 in #221
• ball rolling on a spinning disc by @Peter230655 in #210
• make plot_trajectories work if no input trajectories are given by @Peter230655 in #231
• Ensure number of instance constraints is valid and use inside plot me… by @moorepants in #232
• Drop support for Python 3.8. by @moorepants in #233
• check that equations_of_motion are not AEs by @Peter230655 in #236
• reduced number of frames in animation form 300 to about 75 by @Peter230655 in #242
• New Example: Parameter Identification from Non-Contiguous Measurements by @Peter230655 in #246
• Mississippi steamboat on a lake by @Peter230655 in #208
• Deal with loss of whitespace in Python 3.13. by @moorepants in #254
• Correcting time step width of trajectory plots to equal node_time_int… by @chris-konrad in #283
• Make setuptools a required dependency, fixes #295. by @moorepants in #296
• changed a typo in line 434 by @Peter230655 in #300
• add parse_free method to Problem class, add test fubction by @Peter230655 in #303
• improved HTML rendering by @Peter230655 in #305
• trial push whether layout is o.k. by @Peter230655 in #306
• Testing the RTD preview builds. by @moorepants in #307
• park a car in a garage by @Peter230655 in #289
• docstrings changed for solve to match opty by @Peter230655 in #301
• Allow for one differential equation only. Removed lines near 1300, 1680 by @Peter230655 in #311
• betts 10 103 and 104. Replaces PR # 261 by @Peter230655 in #312
• car around pylons by @Peter230655 in #298
• corrected error in rounding part of the method plot_constraint_violat… by @Peter230655 in #288
• Betts 10 50 by @Peter230655 in #272
• Simplified the code and improve wording/formatting in Betss 10 103-104. by @moorepants in #314
• Load math constants on Windows, fixes #257. by @moorepants in #320
• Added Ackermann & van den Bogert 2010 example. by @moorepants in #29
• Linting, spelling, and wording cleanup on the ball rolling on disc example. by @moorepants in #322
• raise ValueError if duplicate state symbols are present. Fixes #317 by @Peter230655 in #323
• changed I / we wordings by @Peter230655 in #329
• removed I /we wordings, some small changes by @Peter230655 in #328
• Make SciPy an optional dependency, fixes #319. by @moorepants in #327
• removed I wordings by @Peter230655 in #330
• I wording removed by @Peter230655 in #332
• particle-in-tube-new by @Peter230655 in #286
• Break examples into beginner, intermediate, and advanced. Fixes #334 by @moorepants in #338
• Changes ConstraintCollocator attributes to read only properties. Replaces PR #315 by @Peter230655 in #337
• probable typo corrected by @Peter230655 in #341
• removed leading minus by @Peter230655 in #342
• examples-gallery now has three subdirectories by @Peter230655 in #343
• Move the Park 2004 example to the gallery. by @moorepants in #340
• using windows explorer by @Peter230655 in #346
• added more textrm, first attempt at structure as per #348 by @Peter230655 in #350
• Added a sit-to-stand example with the gait2d model. by @moorepants in #356
• Release Version 1.4.0 by @moorepants in #352

New Contributors

• @chris-konrad made their first contribution in #283

Full Changelog: v1.3.0...v1.4.0