Timo Stienstra

Implement numeric solver in KanesMethod

12

#### References to other Issues or PRs Follow up of #24905 related to #24780 #### Brief description of what is fixed or changed This PR implements support in `KanesMethod` for...

Resolving circular imports in physics.vector

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There are various circular dependencies in the `sympy.physics.vector` module. This was also pointed out in #26384, where a new circular import will be added. The aim of this issue is...

Lambdify doesn't recognize derivative symbol if cse is enabled

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Here is a minimal reproducer: ```python >>> import sympy as sm >>> t = sm.symbols("t") >>> x = sm.Function("x")(t) >>> xd = x.diff(t) >>> sm.lambdify((xd, x), xd + x)(1, 1)...

Invalid bounds are ignored without raising a warning or an error

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While debugging one of my own problems. I finally found out one of the reasons it was invalid, namely my bound was just being ignored as it was not directly...

[`determine_free_index`](https://github.com/csu-hmc/opty/blob/0a74a7a08ebd8bc0158e202640d9ad3d010c2d30/opty/direct_collocation.py#L777) in [`_find_closest_free_index`](https://github.com/csu-hmc/opty/blob/0a74a7a08ebd8bc0158e202640d9ad3d010c2d30/opty/direct_collocation.py#L773) assumes that the free variables that are time varying used in the instance constraints are by definition states. This may not actually be the case. A simple...