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Diffstat (limited to 'macros/tf2zp.sci')
| -rw-r--r-- | macros/tf2zp.sci | 150 |
1 files changed, 89 insertions, 61 deletions
diff --git a/macros/tf2zp.sci b/macros/tf2zp.sci index 7c482d5..ca10fd4 100644 --- a/macros/tf2zp.sci +++ b/macros/tf2zp.sci @@ -1,72 +1,100 @@ -// Transfer function to zero pole conversion -//[z,p,k]= tf2zp(b,a); -//z=zeros of the corrsponding tf -//p=poles of the corresponding tf -//k=gain of the tf -//b=vector containing the numerator coefficients of the transfer function in descending powers of s -//a=vector containing the denominator coefficients of the transfer function in descending powers of s -//For discrete-time transfer functions, it is highly recommended to -//make the length of the numerator and denominator equal to ensure -//correct results. You can do this using the function EQTFLENGTH in -//the Signal Processing Toolbox. +// Copyright (C) 2018 - IIT Bombay - FOSSEE // -// -//Author -//Debdeep Dey +// This file must be used under the terms of the CeCILL. +// This source file is licensed as described in the file COPYING, which +// you should have received as part of this distribution. The terms +// are also available at +// http://www.cecill.info/licences/Licence_CeCILL_V2-en.txt +//Original contribution: FOSSEE, IIT Bombay +// Email: toolbox@scilab.in function [z,p,k]=tf2zp(num,den) -numop=argn(1); -//take only the first row of numerator into consideration -num=num(1,:); -//remove leading columns of zeros from numerator -if ~isempty(num) then - while(num(:,1)==0 & length(num)>1) - num(:,1)=[]; - end -end -[rd,cod]=size(den); -[ny,np]=size(num); -if(rd>1) then - error("Denominator must be row vector"); -elseif np>cod then - error("Improper transfer function"); -end -if (~isempty(den)) then - coef=den(1); -else - coef=1; -end -if coef ==0 then - error("Denominator must have non zero leading coefficient"); -end -//remove leading columns of zeros from numerator -if ~isempty(num) then - while(num(:,1)==0 & length(num)>1) - num(:,1)=[]; - end -end + // Transfer function to zero pole conversion -if (find(den==%inf) ~= [] | find(num==%inf) ~= []) then - error("Input to ROOTS must not contain NaN or Inf") -end -//poles + //Calling Sequence + //[z,p,k]= tf2zp(b,a); -p=roots(den); -//zeros and gain + //Parameters + //z=zeros of the corrsponding tf + //p=poles of the corresponding tf + //k=gain of the tf + //b=vector containing the numerator coefficients of the transfer function in descending powers of s/z + //a=vector containing the denominator coefficients of the transfer function in descending powers of s/z -k=zeros(ny,1); -linf=%inf; + //For discrete-time transfer functions, it is highly recommended to + //make the length of the numerator and denominator equal to ensure + //correct results. You can do this using the function EQTFLENGTH in + //the Signal Processing Toolbox. -z=linf(ones(np-1,1),ones(ny,1)); -for i=1:ny - zz=roots(num(i,:)); - if ~isempty(zz), z(1:length(zz), i) = zz; end - ndx = find(num(i,:)~=0); - if ~isempty(ndx), k(i,1) = num(i,ndx(1))./coef; end -end -z=roots(num); -endfunction + //Author : Debdeep Dey + + //Example : + //b = [1 2 3]; + //a = [4 5 6]; + //[z p k] = tf2zp(b,a) + //Output: + //k = + // + // 0.25 + // p = + // + // - 0.625 + 1.0532687i + // - 0.625 - 1.0532687i + // z = + // + // - 1. + 1.4142136i + // - 1. - 1.4142136i + + numop=argn(1); + //take only the first row of numerator into consideration + num=num(1,:); + //remove leading columns of zeros from numerator + if ~isempty(num) then + while(num(:,1)==0 & length(num)>1) + num(:,1)=[]; + end + end + [rd,cod]=size(den); + [ny,np]=size(num); + if(rd>1) then + error("Denominator must be row vector"); + elseif np>cod then + error("Improper transfer function"); + end + if (~isempty(den)) then + coef=den(1); + else + coef=1; + end + if coef ==0 then + error("Denominator must have non zero leading coefficient"); + end + //remove leading columns of zeros from numerator + if ~isempty(num) then + while(num(:,1)==0 & length(num)>1) + num(:,1)=[]; + end + end + if (find(den==%inf) ~= [] | find(num==%inf) ~= []) then + error("Input to ROOTS must not contain NaN or Inf") + end + //poles + p=roots(den); + //zeros and gain + + k=zeros(ny,1); + linf=%inf; + + z=linf(ones(np-1,1),ones(ny,1)); + for i=1:ny + zz=roots(num(i,:)); + if ~isempty(zz), z(1:length(zz), i) = zz; end + ndx = find(num(i,:)~=0); + if ~isempty(ndx), k(i,1) = num(i,ndx(1))./coef; end + end + z=roots(num); +endfunction |