Error converting between sympy and symengine matrices

[oscarbenjamin]

Broken CI in sympy after 0.8.0 release of symengine. I'm not sure what changed but there are now many fails like this in sympy CI:

__ sympy/physics/mechanics/tests/test_joint.py:test_pin_joint_double_pendulum __
Traceback (most recent call last):
  File "/home/runner/work/sympy/sympy/sympy/physics/mechanics/tests/test_joint.py", line 70, in test_pin_joint_double_pendulum
    J1 = PinJoint('J1', C, PartP, speeds=u1, coordinates=q1,
  File "/home/runner/work/sympy/sympy/sympy/physics/mechanics/joint.py", line 494, in __init__
    super().__init__(name, parent, child, coordinates, speeds,
  File "/home/runner/work/sympy/sympy/sympy/physics/mechanics/joint.py", line 145, in __init__
    self._parent_axis = self._axis(parent, parent_axis)
  File "/home/runner/work/sympy/sympy/sympy/physics/mechanics/joint.py", line 246, in _axis
    if not ax.dt(body.frame) == 0:
  File "/home/runner/work/sympy/sympy/sympy/physics/vector/vector.py", line 650, in dt
    return time_derivative(self, otherframe)
  File "/home/runner/work/sympy/sympy/sympy/physics/vector/functions.py", line 198, in time_derivative
    outlist += [(express(v[0], frame,
  File "symengine_wrapper.pyx", line 3690, in symengine.lib.symengine_wrapper.DenseMatrixBase.diff
  File "symengine_wrapper.pyx", line 4067, in symengine.lib.symengine_wrapper.diff
TypeError: Cannot convert symengine.lib.symengine_wrapper.ImmutableDenseMatrix to symengine.lib.symengine_wrapper.Basic

[isuruf]

#366

[oscarbenjamin]

Thanks @isuruf. Does symengine.py do prereleases? Maybe SymPy CI should test those. I'm not sure how easy it would be to setup something that directly tracks symengine.py master.

[isuruf]

We usually don't do pre-releases as many people don't check them. It should easy to track symengine.py master on Linux CI though.