when the program is running, is not entering in the loop

dcs1=hdt.DataCursors
pos = get(dcs1(1),'Position');
    op1 = pos(1)
    op2 = pos(2)
    op=[op1 op2]
    save d.mat op1 op2
    while B<=0
    B=a(op1,op2);
    op2=op2+1;
end
op2=op2-1

Answer 1

[Jan]

Obviously the value of the variable B is greater than 0 initially. You did not show how this variable is defined, so the readers cannot guess this detail.

[supriya kadam]

The image is black and white , so 0 stands for black nd 1 for white , in terms of intensity

[Jan]

Maybe the image is black and white, but what is "B"?

[supriya kadam]

thank u sir. i defined B , and now the program is running

Answer 2

[Jos (10584)]

Apparently B is larger then 0 ... Did you check?