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diff --git a/macros/cheby1.sci b/macros/cheby1.sci new file mode 100644 index 0000000..52ff1ad --- /dev/null +++ b/macros/cheby1.sci @@ -0,0 +1,59 @@ +function [a, b, c, d] = cheby1 (n, rp, w, varargin) +//This function generates a Chebyshev type I filter with rp dB of passband ripple. +//Calling Sequence +//[a, b] = cheby1 (n, rp, w) +//[a, b] = cheby1 (n, rp, w, "high") +//[a, b] = cheby1 (n, rp, [wl, wh]) +//[a, b] = cheby1 (n, rp, [wl, wh], "stop") +//[a, b, c] = cheby1 (…) +//[a, b, c, d] = cheby1 (…) +//[…] = cheby1 (…, "s") +//Parameters +//n: positive integer value +//rp: non negative scalar value +//w: vector, all elements must be in the range [0,1] +//Description +//This is an Octave function. +//This function generates a Chebyshev type I filter with rp dB of passband ripple. +//The fourth parameter takes in high or low, default value is low. The cutoff is pi*Wc radians. +//[b, a] = cheby1(n, Rp, [Wl, Wh]) indicates a band pass filter with edges pi*Wl and pi*Wh radians. +//[b, a] = cheby1(n, Rp, [Wl, Wh], ’stop’) indicates a band reject filter with edges pi*Wl and pi*Wh radians. +//[z, p, g] = cheby1(...) returns filter as zero-pole-gain rather than coefficients of the numerator and denominator polynomials. +//[...] = cheby1(...,’s’) returns a Laplace space filter, w can be larger than 1. +//[a,b,c,d] = cheby1(...) returns state-space matrices. +//Examples +//[a,b,c]=cheby1(2,6,0.7,"high") +//a = +// 1 1 +//b = +// -0.62915 + 0.55372i -0.62915 - 0.55372i +//c = 0.055649 + +rhs = argn(2) +lhs = argn(1) +[rows,columns] = size(w) +if(rhs>5 | rhs<3) +error("Wrong number of input arguments.") +end +if(lhs>4 | lhs<2) +error("Wrong number of output arguments.") +end + + select (rhs) + case 3 then + if (lhs==2) [a,b] = callOctave("cheby1",n, rp, w) + elseif (lhs==3) [a,b,c] = callOctave("cheby1",n, rp, w) + elseif (lhs==4) [a,b,c,d] = callOctave("cheby1",n, rp, w) + end + case 4 then + if (lhs==2) [a,b] = callOctave("cheby1",n, rp, w, varargin(1)) + elseif (lhs==3) [a,b,c] = callOctave("cheby1",n, rp, w, varargin(1)) + elseif (lhs==4) [a,b,c,d] = callOctave("cheby1",n, rp, w, varargin(1)) + end + case 5 then + if (lhs==2) [a,b] = callOctave("cheby1",n, rp, rs, w, varargin(1), varargin(2)) + elseif (lhs==3) [a,b,c] = callOctave("cheby1",n, rp, rs, w, varargin(1), varargin(2)) + elseif (lhs==4) [a,b,c,d] = callOctave("cheby1",n, rp, rs, w, varargin(1), varargin(2)) + end + end +endfunction |