plotting graphs from every changing loop in matlab -

i strange problem in matlab code, part of code:

for k=1:length(box11)     num_pts1(k)=sum(length(find(box11(:,k)>0)));     size1=sum(length(find(box11(:,:)>0)));     perc1(k)=(num_pts1(k)/size1)*100; end plot(delta,perc1(k),'*') 

however, problem perc1 fixed in plot. see straight line in graph. have different numbers give curve line me because k changing every loop graph should change .. plzzzzzzzzzzzzzzzz, :( !!!

provided box11 matrix contain different number of elements >0 per column, code works fine. think problem data, not code. following tidied version of code dummy data , works ok:

% create dummy box11 matrix box11 = round(rand(15,58));  % pre-allocate variables num_pts1 = zeros(length(box11),1);  k=1:length(box11)     num_pts1(k)=sum(length(find(box11(:,k)>0)));        end  size1=sum(length(find(box11(:,:)>0))); perc1=(num_pts1/size1)*100; delta = 1:length(perc1);  plot(delta,perc1,'*') 

it produces following plot (in octave, should similar in matlab):