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Diffstat (limited to 'macros/cheby2.sci~')
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diff --git a/macros/cheby2.sci~ b/macros/cheby2.sci~ new file mode 100644 index 0000000..9efd721 --- /dev/null +++ b/macros/cheby2.sci~ @@ -0,0 +1,58 @@ +function [a, b, c, d] = cheby2 (n, rs, w, varargin) +//This function generates a Chebyshev type II filter with rs dB of stopband attenuation. +//Calling Sequence +//[a, b] = cheby2 (n, rs, wc) +//[a, b] = cheby2 (n, rs, wc, "high") +//[a, b] = cheby2 (n, rs, [wl, wh]) +//[a, b] = cheby2 (n, rs, [wl, wh], "stop") +//[a, b, c] = cheby2 (…) +//[a, b, c, d] = cheby2 (…) +//[…] = cheby2 (…, "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 II filter with rs dB of stopband attenuation. +//The fourth parameter takes in high or low, default value is low. The cutoff is pi*Wc radians. +//[b, a] = cheby2(n, Rp, [Wl, Wh]) indicates a band pass filter with edges pi*Wl and pi*Wh radians. +//[b, a] = cheby2(n, Rp, [Wl, Wh], ’stop’) indicates a band reject filter with edges pi*Wl and pi*Wh radians. +//[z, p, g] = cheby2(...) returns filter as zero-pole-gain rather than coefficients of the numerator and denominator polynomials. +//[...] = cheby2(...,’s’) returns a Laplace space filter, w can be larger than 1. +//[a,b,c,d] = cheby2(...) returns state-space matrices. +//Examples +//[a,b,c]=cheby2(2,5,0.7,"high") +//a = +// -0.31645 - 0.94861i -0.31645 + 0.94861i +//b = +// -0.39388 + 0.53138i -0.39388 - 0.53138i +//c = 0.47528 + +rhs = argn(2) +lhs = argn(1) + +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("cheby2",n, rp, w) + elseif (lhs==3) [a,b,c] = callOctave("cheby2",n, rp, w) + elseif (lhs==4) [a,b,c,d] = callOctave("cheby2",n, rp, w) + end + case 4 then + if (lhs==2) [a,b] = callOctave("cheby2",n, rp, w, varargin(1)) + elseif (lhs==3) [a,b,c] = callOctave("cheby2",n, rp, w, varargin(1)) + elseif (lhs==4) [a,b,c,d] = callOctave("cheby2",n, rp, w, varargin(1)) + end + case 5 then + if (lhs==2) [a,b] = callOctave("cheby2",n, rp, rs, w, varargin(1), varargin(2)) + elseif (lhs==3) [a,b,c] = callOctave("cheby2",n, rp, rs, w, varargin(1), varargin(2)) + elseif (lhs==4) [a,b,c,d] = callOctave("cheby2",n, rp, rs, w, varargin(1), varargin(2)) + end + end |