firwin (pyleoclim.utils.filter.firwin)

pyleoclim.utils.filter.firwin(ys, fc, numtaps=None, fs=1, pad='reflect', window='hamming', reflect_type='odd', params=(1, 0, 0), padFrac=0.1, **kwargs)[source]

Applies a Finite Impulse Response filter design with window method and frequency fc, with padding

Parameters

  • ys (numpy array) – Timeseries

  • fc (float or list) – cutoff frequency. If scalar, it is interpreted as a low-frequency cutoff (lowpass) If fc is a list, it is interpreted as a frequency band (f1, f2), with f1 < f2 (bandpass)

  • numptaps (int) – Length of the filter (number of coefficients, i.e. the filter order + 1). numtaps must be odd if a passband includes the Nyquist frequency. If None, will use the largest number that is smaller than 1/3 of the the data length.

  • fs (float) – sampling frequency

  • window (str or tuple of string and parameter values, optional) – Desired window to use. See scipy.signal.get_window for a list of windows and required parameters.

  • pad (string) – Indicates if padding is needed. - ‘reflect’: Reflects the timeseries - ‘ARIMA’: Uses an ARIMA model for the padding - None: No padding.

  • params (tuple) – model parameters for ARIMA model (if pad = True)

  • padFrac (float) – fraction of the series to be padded

  • kwargs (dict) – a dictionary of keyword arguments for scipy.signal.firwin

Returns

yf – filtered array

Return type

array

See also

scipy.signal.firwin

FIR filter design using the window method