Week 2025 01

[moorepants]

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[moorepants]

I tried to use linear_eq_to_matrix() but it fails:

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
Cell In[80], line 3
      1 unknowns = sm.Matrix([L1, L2, L3, L4, L5, L6])
----> 3 coef_mat, rhs = sm.linear_eq_to_matrix(exprs, unknowns)
      5 sol = coef_mat.LUsolve(rhs)
      7 sm.Eq(unknowns, sol)

File ~/miniconda/envs/multibody-book/lib/python3.11/site-packages/sympy/solvers/solveset.py:2628, in linear_eq_to_matrix(equations, *symbols)
   2626 # construct the dictionaries
   2627 try:
-> 2628     eq, c = _linear_eq_to_dict(equations, symbols)
   2629 except PolyNonlinearError as err:
   2630     raise NonlinearError(str(err))

File ~/miniconda/envs/multibody-book/lib/python3.11/site-packages/sympy/polys/matrices/linsolve.py:154, in _linear_eq_to_dict(eqs, syms)
    152 coeffs = []
    153 ind = []
--> 154 symset = set(syms)
    155 for i, e in enumerate(eqs):
    156     if e.is_Equality:

TypeError: unhashable type: 'MutableDenseMatrix'