# [SciPy-User] freqz -style plot of "window design" FIR?

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## [SciPy-User] freqz -style plot of "window design" FIR?

 I’m trying to design an arbitrary frequency response filter as described here:http://www.dspguide.com/ch17/1.htmThe technique is said to result in an impulse response in time domain and later in to a filter kernel.I’ve been using scipy.signal.freqz to make magnitude response plots:e.g.fs = 44100# Design a low-pass filter using remez.cutoff = 2000.0transition_width = 200bands = np.array([0, cutoff - 0.5*transition_width,                  cutoff + 0.5*transition_width, fs/2.0]) / fsdesired = [1, 0]lpf = remez(513, bands, desired)# Plot the frequency response of the filter.w, h = freqz(lpf)plt.figure(1)plt.plot(fs*w/(2*np.pi), 20*np.log10(abs(h)))plt.xlim(0, fs/2)plt.xlabel('Frequency (Hz)')plt.ylabel('Gain (dB)')plt.grid(True)But my question is, if using the above arbitrary frequency response design technique, would I be able to use freqz?freqz takes as a parameter “numerator of a linear filter” and remez is returning an array of coefficients, which I read to be the same thing.But in the case of the arbitrary frequency response filter, what can I put into freqz? Is filter kernel perhaps the same as coefficients?_______________________________________________ SciPy-User mailing list [hidden email] https://mail.scipy.org/mailman/listinfo/scipy-user