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scipy.signal.cheb2ap

# scipy.signal.cheb1ap

`scipy.signal.``cheb1ap`(N, rp)

  Return (z,p,k) for Nth order Chebyshev type I analog lowpass filter.

  The returned filter prototype has rp decibels of ripple in the passband.

  The filter’s angular (e.g. rad/s) cutoff frequency is normalized to 1, defined as the point at which the gain first drops below `-rp`.