Why I don't get any results from this code?

I run the following code:

for ii = length(pks4)  %repeat the following process as many times as the pks4 points are
    for k2 = (pks4(ii):xfb(end)); % for all k2 that belong between pks4 and the end of index
        first2(ii) = k2(k2>xfb2); %find all k2 such that k2 is greater than xfb2
        if ~isempty(first2)
            first2 = first2(1);  % store the first number (first2) which is greater than xfb2
        else
            disp('No value of k2 is greater than xfb2.')
        end
        distS(ii) = size(pks4(ii):first2(ii)); % distance between each pks4 and first2 points
        mean_distS = mean(numPointsS(ii));  % mean distS
        Send = locs_SwaveB*mean_distS;  %location of S point
    end
end

but in the end I get neither an error message nor any results. What's wrong with this code? And why Matlab doesn't give any error messages?

Thanks in advance for any help.

Answer 1

[Walter Roberson]

The first length(pks4) entries in pks4 might all be greater than xfb(end) so the inner loop might never execute.

Caution: you have

   first2(ii) = k2(k2>xfb2); %find all k2 such that k2 is greater than xfb2

Your comment implies there might be multiple k2 entries that fit the criteria, so the right hand side might be a vector, but you are trying to assign it into location that only fits a scalar.

[Konstantinos]

but even if I change "for ii=length(pks3)" to "for ii=1:length(pks3)", I don't get any message in the end

[Walter Roberson]

Put in a breakpoint on the outer for loop and run the code. When it stops, display xfb(end) and display pks4 and display nnz(pks4>xfb(end))

[Konstantinos]

What's the point of the breakpoint? I tried it and didn't see anything useful after the displays.

[Walter Roberson]

If you show us the output then we might be able to figure out why the loop is not working.