


A
      tensor([[[1., 0.],
               [0., 1.]],



          [[2., 0.],
           [0., 2.]]])
  >>> torch.linalg.matrix_exp(A)
  tensor([[[2.7183, 0.0000],
           [0.0000, 2.7183]],

           [[7.3891, 0.0000],
            [0.0000, 7.3891]]])

  >>> import math
  >>> A = torch.tensor([[0, math.pi/3], [-math.pi/3, 0]]) # A is skew-symmetric
  >>> torch.linalg.matrix_exp(A) # matrix_exp(A) = [[cos(pi/3), sin(pi/3)], [-sin(pi/3), cos(pi/3)]]
  tensor([[ 0.5000,  0.8660],
          [-0.8660,  0.5000]])
