def test_cwt_coefficients(self):
        x = [0.1, 0.2, 0.3]
        param = [
            {"widths": (1, 2, 3), "coeff": 2, "w": 1},
            {"widths": (1, 3), "coeff": 2, "w": 3},
            {"widths": (1, 3), "coeff": 5, "w": 3},
        ]
        shuffle(param)

        expected_index = [
            "coeff_2__w_1__widths_(1, 2, 3)",
            "coeff_2__w_3__widths_(1, 3)",
            "coeff_5__w_3__widths_(1, 3)",
        ]

        res = cwt_coefficients(x, param)
        res = pd.Series(dict(res))

        # todo: add unit test for the values
        self.assertCountEqual(list(res.index), expected_index)
        self.assertTrue(math.isnan(res["coeff_5__w_3__widths_(1, 3)"]))