docs: def lstsq(A, b):
      r"""Return the least-squares solution to a linear matrix equation.
  
      Args:
          A (array_like): Coefficient matrix.
          b (array_like): Ordinate values.
  
      Returns:
          :class:`numpy.ndarray`: Least-squares solution.
      """
      A = asarray(A, float)
      b = asarray(b, float)
  
      if A.ndim == 1:
          A = A[:, newaxis]
  
      if A.shape[1] == 1:
          return dot(A.T, b) / squeeze(dot(A.T, A))
  
      rcond = finfo(double).eps * max(*A.shape)
      return npy_lstsq(A, b, rcond=rcond)[0]