How to index a matrix using the ITERATION values of a valArray with non-consecutive numbers?

Hi everyone, New to matlab here and I can't seem to find a previous answer to this question.

I'm trying to populate a matrix element by element using a for loop, but I'm running into a problem. Because of the way I need it to load in the data, I have the subject numbers listed in a valArray for the for loop. This works fine for loading, but when I try to index the matrix, it puts it the value in the element of the actual VALUE of the number, whereas I want it to be in the element of the iteration number it represents. Here's what I have:

for s = [1297 1304]

      for b = 1:2

          datafilename=sprintf('none_mod_part_data_gamma1.25_%d_Block%03d.mat',s,b);
          %datafile=[datadir,datafilename];

          load(datafilename);

          GE_byblock(b)= GE_pos(1);
          LE_byblock(b)=mean(LE_pos{1});
          ...

      end;

      LE_allsubs_avg(s) = mean(LE_byblock);
      LE_allsubs_std(s) = std(LE_byblock);

      GE_pos_allsubs_avg(s) = mean(GE_byblock);
      GE_pos_allsubs_std(s) = std(GE_byblock);

      ...
  end;

So what I want is for the value I have produced for subject 1297 to go in element ONE of the LE_allsubs_avg matrix and the value for subject 1304 to go in element TWO of the allsubs matrix, etc. But what I get is the value for subject 1297 going into element 1297 of the allsubs matrix. Any way I can remedy this, or do I have to make a new loop somehow with i=1:number of subjects?

Additionally, I have previously in the code initialized all the matrices to their correct sizes.

Thanks so much- any help is greatly appreciated!!!

Answer 1

[Kelly Kearney]

There are two ways you could do this. One is to use an index value corresponding to the length of your s values:

s = [1297 1304]
for is = 1:length(s)
  % ... code here, replacing previous s with s(is)
  LE_allsubs_avg(is) = ...
end

Alternatively, you could add a counter variable:

count = 1;
for s = [1297 1307]
  % code here
  LE_allsubs_avg(count) = ...
  count = count + 1
end

[Kel]

This worked perfectly! Thank you so much for your help, I really appreciate it!