'Determine whether the matrix has sorted indices
Returns
- True: if the indices of the matrix are in sorted order
- False: otherwise'

def __get_sorted(self):

    if (not hasattr(self, '_has_sorted_indices')):
        self._has_sorted_indices = _sparsetools.csr_has_sorted_indices((len(self.indptr) - 1), self.indptr, self.indices)
    return self._has_sorted_indices
