@modifies
    @collective
    def zero_rows(self, rows, diag_val=1.0):
        base._trace.evaluate(set([self]), set([self]))
        self._assemble()
        rows = rows.indices if isinstance(rows, Subset) else rows
        self.handle.zeroRowsLocal(rows, diag_val)
Zeroes the specified rows of the matrix, with the exception of the
dataset/ETHPy150Open OP2/PyOP2/pyop2/petsc_base.py/Mat.zero_rows