4afdc53218ffc1356c008ef2e4a3c4c5d4f1795e,scipy/signal/tests/test_filter_design.py,TestCheb1ord,test_lowpass,#TestCheb1ord#,197

Before Change

class TestCheb1ord(TestCase):

    def test_lowpass(self):
        n, Wn = cheb1ord(0.2, 0.3, 3, 60)
        assert_equal(n, 8)
        assert_allclose(Wn, 0.2, rtol=1e-15)

After Change

class TestCheb1ord(TestCase):

    def test_lowpass(self):
        wp = 0.2
        ws = 0.3
        rp = 3
        rs = 60
        N, Wn = cheb1ord(wp, ws, rp, rs, False)
        b, a = cheby1(N, rp, Wn, "low", False)
        w, h = freqz(b, a)
        w /= np.pi
        assert_array_less(-rp - 0.1, dB(h[w <= wp]))
        assert_array_less(dB(h[ws <= w]), -rs + 0.1)

Instances