Return a Blackman window.
The Blackman window is a taper formed by using the first three terms of
a summation of cosines. It was designed to have close to the minimal
leakage possible. It is close to optimal, only slightly worse than a
Kaiser window. [...]
Return the Discrete Fourier Transform sample frequencies.
The returned float array f contains the frequency bin centers in cycles
per unit of the sample spacing (with zero at the start). For instance, if
the sample spacing is in seconds, then the frequency unit is cycles/second.
Given a window length n and a sample spacing d::
f = 0, 1, ..., n/2-1, -n/2, ..., -1 / (dn) if n is even
f = 0, 1, ..., (n-1)/2, -(n-1)/2, ..., -1 / (dn) if n is odd [...]
FIR filter design using the window method.
This function computes the coefficients of a finite impulse response
filter. The filter will have linear phase; it will be Type I if
numtaps is odd and Type II if numtaps is even.
Type II filters always have zero response at the Nyquist frequency, so a
ValueError exception is raised if firwin is called with numtaps even and
having a passband whose right end is at the Nyquist frequency. [...]
Compute the attenuation of a Kaiser FIR filter.
Given the number of taps N and the transition width width, compute the
attenuation a in dB, given by Kaiser's formula:
a = 2.285 * (N - 1) * pi * width + 7.95 [...]