'Swap the two given columns of the matrix in-place.
Examples
>>> from sympy.matrices import Matrix
>>> M = Matrix([[1, 0], [1, 0]])
>>> M
Matrix([
[1, 0],
[1, 0]])
>>> M.col_swap(0, 1)
>>> M
Matrix([
[0, 1],
[0, 1]])
See Also
col
row_swap'

def col_swap(self, i, j):

    for k in range(0, self.rows):
        (self[(k, i)], self[(k, j)]) = (self[(k, j)], self[(k, i)])
