related to image processing

hi, I have made the following program which is used for refinement in image coding. mark=zeros(1,4); out1=zeros(1,4); out=zeros(1,4); x=[1 3 7 8]; for n=3:-1:1; t=2^n; for i=1:4; if (x(i)>=t);

        switch mark(i)
            case 0
                out1(i)=sign(x(i));
                mark(i)=1;

            case 1
                z=dec2bin(x(i),4);
                out1(i)=z(1);
                mark(i)=2;
            case 2
                z1=dec2bin(x(i),4);
                out1(i)=z1(2);
                mark(i)=3;

            otherwise
        end
    else
        out1(i)=0;
    end

    end
end

when I run this program I get finally out1 as 0 1 48 48 . Instead I should get 0 1 0 0. Can any body tell me what is the problem with my program.

[Mischa Kim]

Answered in your duplicate question.