(self, j, f)
In-place operation on col j using two-arg functor whose args are
        interpreted as (self[i, j], i) for i in range(self.rows).

        Examples
        ========

        >>> from sympy.matrices import SparseMatrix
        >>> M = SparseMatrix.eye(3)*2
        >>> M[1, 0] = -1
        >>> M.col_op(1, lambda v, i: v + 2*M[i, 0]); M
        Matrix([
        [ 2, 4, 0],
        [-1, 0, 0],
        [ 0, 0, 2]])
In-place operation on col j using two-arg functor whose args are
        interpreted as (self[i, j], i) for i in range(self.rows).
In - place operation on col j using two - arg functor whose args are interpreted as ( self [ i j ] i ) for i in range ( self . rows ) .
def col_op(self, j, f):
        """In-place operation on col j using two-arg functor whose args are
        interpreted as (self[i, j], i) for i in range(self.rows).

        Examples
        ========

        >>> from sympy.matrices import SparseMatrix
        >>> M = SparseMatrix.eye(3)*2
        >>> M[1, 0] = -1
        >>> M.col_op(1, lambda v, i: v + 2*M[i, 0]); M
        Matrix([
        [ 2, 4, 0],
        [-1, 0, 0],
        [ 0, 0, 2]])
        """
        for i in range(self.rows):
            v = self._smat.get((i, j), S.Zero)
            fv = f(v, i)
            if fv:
                self._smat[(i, j)] = fv
            elif v:
                self._smat.pop((i, j))
def col_op ( self , j , f ) : for i in range ( self . rows ) : v = self . _smat . get ( ( i , j ) , S . Zero ) fv = f ( v , i ) if fv : self . _smat [ ( i , j ) ] = fv elif v : self . _smat . pop ( ( i , j ) )