Use loop for indexing

I'm trying to retriev an index from data by passing labels from 1 to 2 but the for loop is not changing?

      clc;
      clear all;
      close all;
     %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
       c=2;
       labels =[2,1,2,1,2,1,2,1,2,2];
       data =[-26.152,0.59028;2.0480,1.1151;-16.680,0.704710;8.2308,1.1567;-14.1760,-0.879840;
       7.81450,0.7927;-20.220,0.992;8.921,0.822;-16.507,0.5297;-11.212,-1.6457];
       colors={'r.' 'gx' 'b+' 'ys' 'md' 'cv' 'k.' 'r*' 'g*' 'b*' 'y*' 'm*' 'c*' 'k*' };
     %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   for i=1:c
           index = find(labels == i);

           if ~isempty(index)

            dat=data(index,:);

            plot(dat(:,1),dat(:,2),colors{i})
           end
       end
      for i=1:c
      index=find(labels == 1);
      f0(index,i)=1;
     end   
   result.data.f=f0;
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
i=2 not 1, 2

[Geoff Hayes]

shawin - why do you expect i to be 1,2? You have two for loops, so when the second one iterates over 1 and 2 so it will be assigned a value of 2 when the loop completes. Try using the debugger to step through the code and see this.

Answer 1

[Jan]

Use the auto-indentation to get clear code:

for i=1:c
   index = find(labels == i);
   if ~isempty(index)
      dat=data(index,:);
      plot(dat(:,1),dat(:,2),colors{i})
   end
end

for i=1:c
   index=find(labels == 1);
   f0(index,i)=1;
end

Perhaps "i=2 not 1, 2 " means the second loop. Is "labels == 1" a typo and you meant "labels == i" as in the first loop?

By the way: "logical indexing" is faster:

for k = 1:c
   index        = (labels == k);  % Without FIND
   f0(index, k) = 1;
end