(k, n) (default)
       * "'some=False'": returns *(Q, R)* with dimensions (m, m),
         (m, n)

Keyword Arguments:
      out (tuple, optional) -- tuple of Q and R tensors.
      The dimensions of Q and R are detailed in the description of
      "some" above.
Example:
  >>> a = torch.tensor([[12., -51, 4], [6, 167, -68], [-4, 24, -41]])
  >>> q, r = torch.qr(a)
  >>> q
  tensor([[-0.8571,  0.3943,  0.3314],
          [-0.4286, -0.9029, -0.0343],
          [ 0.2857, -0.1714,  0.9429]])
  >>> r
  tensor([[ -14.0000,  -21.0000,   14.0000],
          [   0.0000, -175.0000,   70.0000],
          [   0.0000,    0.0000,  -35.0000]])
  >>> torch.mm(q, r).round()
  tensor([[  12.,  -51.,    4.],
          [   6.,  167.,  -68.],
          [  -4.,   24.,  -41.]])
  >>> torch.mm(q.t(), q).round()
  tensor([[ 1.,  0.,  0.],
          [ 0.,  1., -0.],
          [ 0., -0.,  1.]])
