Im trying to make an 4th Order Chebyshev, with these settings. Wp = 0.9999;

Ws = .0250;

Rp = 1;

Rs = 50;

[n,Wp] = cheb1ord(Wp,Ws,Rp,Rs)

n = 4

[b,a] = cheby1(n,Rp,Wp);

freqz(b,a,500,200)

title('n = 4th Order Chebyshev Type I ECG Lowpass Filter')

I want my cutoff frequency to be 40Hz by using Wp/Ws. (I believe thats the cutofff frequency for the cheby?) And once those variables are saved and I enter [n,Wp] = cheb1ord(Wp,Ws,Rp,Rs), my n changes to 1. Why is that?

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