Can someone tell me what my mistake is?

    [A,map]=imread('C:\Users\s514835\Desktop\calvinhobbs.gif');

    B=im2double(A);

    imshow(B);colormap(gray)

    [u,s,v]=svd(B);

    C=zeros(size(B));
    for j=1:30
        C=C+s(j,j)*u(:,j)*v(:,j).';
    end

    figure
    imshow(C,[]);colormap(gray)
    drawnow

[Stephen23]

We can't read your mind and "know" what that code "should" do. How do we know what your algorithm is? You need to help us understand by actually explaining what you expect to happen, and what is currently happening with the code that you have.

Answer 1

[Image Analyst]

Well two of them are not having comments, and not formatting your code for this forum. The latter can be fixed by viewing this. I guess a third thing is not telling us what you think is wrong, or telling us any error messages. That can be fixed by reading this.