fsvd.m

MFD－多变量系统频域设计工具

function [u,s,v]=fsvd(w,f)
%FSVD   Singular values of MVFR matrix.
%       FSVD(W,F) returns the singular values, one row per
%       frequency, of the component matrices of the MVFR matrix, F.
%
%       [U,S,V]=FSVD(W,F)  returns the U,S,V matrices as MVFR
%       matrices whose component matrices are
%       [Um,Sm,Vm]=svd(Fm)
%       where Fm are the component matrices of F.
%       Refer to SVD for the format of the component
%       matrices  Um, Sm and Vm.
%       See also FEIG

%       Dr M.P. Ford 4th August 1987
% Copyright (c) 1987 by GEC Engineering Research Centre & Cambridge Control Ltd

nargs=nargout;
[m,n]=fsize(w,f);
mn=min(m,n);
lw=length(w);
k=1:m;            % vector of rows of each matrix in F
p=1:n;
if nargs==3     % both singular values and matrices required
  s=zeros(lw*m,n); % Set up output matrix for values
  u=zeros(lw*m,m); % Set up output matrix for vectors
  v=zeros(lw*n,n);
  for i=1:lw       % for each frequency
     [uvec,sval,vvec]=svd(f(k+(i-1)*m,:));
     u(k+m*(i-1),:)=uvec;
     s(k+m*(i-1),:)=sval;
     v(p+n*(i-1),:)=vvec;
  end % for i=1:lw
elseif nargs==1  % only singular values required
  u=zeros(lw,mn);   % Set up output matrix for values
  for i=1:lw        % for each frequency
     u(i,:)=svd(f(k+(i-1)*m,:)).';  % transpose singular values
  end % for i=1:lw
else
  error('Must have 1 or 3 output arguments');
end  % else