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Diffstat (limited to 'macros/ellip.sci')
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diff --git a/macros/ellip.sci b/macros/ellip.sci new file mode 100644 index 0000000..264d9fe --- /dev/null +++ b/macros/ellip.sci @@ -0,0 +1,60 @@ +function [a, b, c, d] = ellip (n, rp, rs, w, varargin) +//This function generates an elliptic or Cauer filter with rp dB of passband ripple and rs dB of stopband attenuation. +//Calling Sequence +//[a, b] = ellip (n, rp, rs, wp) +//[a, b] = ellip (n, rp, rs, wp, "high") +//[a, b] = ellip (n, rp, rs, [wl, wh]) +//[a, b] = ellip (n, rp, rs, [wl, wh], "stop") +//[a, b, c] = ellip (…) +//[a, b, c, d] = ellip (…) +//[…] = ellip (…, "s") +//Parameters +//n: positive integer value +//rp: non negative scalar value +//rs: non negative scalar value +//w: scalar or vector, all elements should be in the range [0,1] +//Description +//This is an Octave function. +//This function generates an elliptic or Cauer filter with rp dB of passband ripple and rs dB of stopband attenuation. +//[b, a] = ellip(n, Rp, Rs, Wp) indicates low pass filter with order n, Rp decibels of ripple in the passband and a stopband Rs decibels down and cutoff of pi*Wp radians. If the fifth argument is high, then the filter is a high pass filter. +//[b, a] = ellip(n, Rp, Rs, [Wl, Wh]) indictaes band pass filter with band pass edges pi*Wl and pi*Wh. If the fifth argument is stop, the filter is a band reject filter. +//[z, p, g] = ellip(...) returns filter as zero-pole-gain. +//[...] = ellip(...,’s’) returns a Laplace space filter, w can be larger than 1. +//[a, b, c, d] = ellip(...) returns state-space matrices. +//Examples +//[a,b]=ellip(2, 0.5, 0.7, [0.3,0.4]) +//a = +// 0.88532 -1.58410 2.40380 -1.58410 0.88532 +//b = +// 1.00000 -1.78065 2.68703 -1.75725 0.97454 + +rhs = argn(2) +lhs = argn(1) +if(rhs>3) +[rows,columns] = size(w) +end +if(rhs>6 | rhs<4) +error("Wrong number of input arguments.") +end +if(lhs>4 | lhs<2) +error("Wrong number of output arguments.") +end + +select (rhs) + case 4 then + if (lhs==2) [a,b] = callOctave("ellip",n, rp, rs, w) + elseif (lhs==3) [a,b,c] = callOctave("ellip",n, rp, rs, w) + elseif (lhs==4) [a,b,c,d] = callOctave("ellip",n, rp, rs, w) + end + case 5 then + if (lhs==2) [a,b] = callOctave("ellip",n, rp, rs, w, varargin(1)) + elseif (lhs==3) [a,b,c] = callOctave("ellip",n, rp, rs, w, varargin(1)) + elseif (lhs==4) [a,b,c,d] = callOctave("ellip",n, rp, rs, w, varargin(1)) + end + case 6 then + if (lhs==2) [a,b] = callOctave("ellip",n, rp, rs, w, varargin(1), varargin(2)) + elseif (lhs==3) [a,b,c] = callOctave("ellip",n, rp, rs, w,varargin(1), varargin(2)) + elseif (lhs==4) [a,b,c,d] = callOctave("ellip",n, rp, rs, w, varargin(1), varargin(2)) + end + end +endfunction |