signalproc.py 文件源码

def highpass_cnt(data, low_cut_hz, fs, filt_order=3, axis=0):
    """
     Highpass signal applying **causal** butterworth filter of given order.

    Parameters
    ----------
    data: 2d-array
        Time x channels
    low_cut_hz: float
    fs: float
    filt_order: int

    Returns
    -------
    highpassed_data: 2d-array
        Data after applying highpass filter.
    """
    if (low_cut_hz is None) or (low_cut_hz == 0):
        log.info("Not doing any highpass, since low 0 or None")
        return data.copy()
    b, a = scipy.signal.butter(filt_order, low_cut_hz / (fs / 2.0),
                               btype='highpass')
    assert filter_is_stable(a)
    data_highpassed = scipy.signal.lfilter(b, a, data, axis=axis)
    return data_highpassed