test_evoked.py 文件源码

def test_savgol_filter():
    """Test savgol filtering
    """
    h_freq = 10.
    evoked = read_evokeds(fname, 0)
    freqs = fftpack.fftfreq(len(evoked.times), 1. / evoked.info['sfreq'])
    data = np.abs(fftpack.fft(evoked.data))
    match_mask = np.logical_and(freqs >= 0, freqs <= h_freq / 2.)
    mismatch_mask = np.logical_and(freqs >= h_freq * 2, freqs < 50.)
    assert_raises(ValueError, evoked.savgol_filter, evoked.info['sfreq'])
    evoked_sg = evoked.copy().savgol_filter(h_freq)
    data_filt = np.abs(fftpack.fft(evoked_sg.data))
    # decent in pass-band
    assert_allclose(np.mean(data[:, match_mask], 0),
                    np.mean(data_filt[:, match_mask], 0),
                    rtol=1e-4, atol=1e-2)
    # suppression in stop-band
    assert_true(np.mean(data[:, mismatch_mask]) >
                np.mean(data_filt[:, mismatch_mask]) * 5)
    # original preserved
    assert_allclose(data, np.abs(fftpack.fft(evoked.data)), atol=1e-16)