I need to alter an FIR filter which I know very little about. I have a signal which need to be altered, and looking at a Python script used for this task, I see that it uses Scipy's signal library, more specifically the
If I input
cutoff_freq = 5400 num_taps = 51 coeffs = signal.firwin(numtaps = num_taps, cutoff = cutoff_freq, window = "hamming", nyq = 72000)
scipy\signal\filter_design.py:338: BadCoefficients: Badly conditioned filter coefficients (numerator): the results may be meaningless
The same occurs when
num_taps is 52, 53, 54 and 55, but 56, 57, 58 and 59 does not give this warning.
What does this mean and how should I be sure to avoid it?