MATLAB-a.rar_algorithms

function [B] = adj(A,mode) %ADJ Matrix adjoint. % % ADJ(A) is the adjoint matrix of matrix A. % A may be complex and any size, RxC % % usage: B = adj(A) % % If R <= C then the Right Adjoint is returned % If R >= C then the Left Adjoint is returned % % The inverse of A is: INV(A) = ADJ(A)/det(A). % Matrices that are not invertable still have an adjoint. % % See also SVD, PINV, INV, RANK, SLASH, DETT %Paul Godfrey, October, 2006 [r,c]=size(A); [u,s,v]=svd(A); k=det(u)*det(v'); if r==1 | c==1, s=s(1); end s=diag(s); if exist('mode','var') B=k*prod(s)*pinv(A); else for n=1:length(s) p=s; p(n)=[]; V(:,n)=k*prod(p)*v(:,n); end B=V*u(:,1:length(s))'; end return syms m %Demos of this program are: clc A=[-m 1 0;0 -m 1;-18 -27 -10-m] aa=adj(A) disp('ADJOINT') a*aa