% Extended Powell Singular function% --------------------------------- %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% function [fvec,J]=singx(n,m,x,option)% Dimensions -> n=variable but a multiple of 4, m=n             % Problem no. 22% Standard starting point -> x=(s(j)) where %                            s(4*j-3)=3, %                            s(4*j-2)=-1,%                            s(4*j-1)=0,%                            s(4*j)=1 % Minima -> f=0 at the origin.            %                                     % 11/21/94 by Madhu Lamba  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%function [fvec,J] = singx(n,m,x,option)  J=zeros(m,n);for i=1:m/4   if (option==1 | option==3)        fvec(4*i-3)=x(4*i-3)+10*(x(4*i-2));        fvec(4*i-2)=sqrt(5)*(x(4*i-1)-x(4*i));        fvec(4*i-1)=(x(4*i-2)-2*(x(4*i-1)))^2;        fvec(4*i)  =sqrt(10)*(x(4*i-3)-x(4*i))^2;   end;           if (option==2 | option==3)	J(4*i-3,4*i-3) = 1;        J(4*i-3,4*i-2) = 10;        J(4*i-2,4*i-1) = sqrt(5);        J(4*i-2,4*i)   = -sqrt(5);        J(4*i-1,4*i-2) = 2*x(4*i-2)-4*x(4*i-1);        J(4*i-1,4*i-1) = 8*x(4*i-1)-4*x(4*i-2);        J(4*i,4*i-3)   = 2*sqrt(10)*(x(4*i-3)-x(4*i));        J(4*i,4*i)     = 2*sqrt(10)*(x(4*i)-x(4*i-3));   end;end;if (option==1 | option==3)   fvec=fvec';end;%