@property
    def is_upper(self):
        return all(self[i, j].is_zero
            for i in range(1, self.rows)
            for j in range(i))
Test cluster level permutations T-test
dataset/ETHPy150Open sympy/sympy/sympy/matrices/matrices.py/MatrixBase.is_upper--crossover with--dataset/ETHPy150Open mne-tools/mne-python/mne/stats/tests/test_cluster_level.py/test_cluster_permutation_t_test