Indexing a variable

Hi,

I'm looking for some guidance on how you would index variables. I have read a couple of forums but with no clear picture.

I have looped a matrix array (5x1) of a numerical form to obtain a string output of 5 ".mat" files that has data stored in them. What I want to do next is Load these .mat files in a loop and let Matlab iterate it for each file such that I get my plots for each (or string in this case).

A simple example, for loop output --> mat files = A_1, A_2, A_3, A_4, A_5

load A_1, A_2, A_3, A_4, A_5 each time to create the plots. (?) or extend the above for-loop further to load the file each iteration. (?)

Now, I could load each file each time and get the results (load A_1 then load A_2 etc...) But if there could be some sort of a variable counter that would be great (less work... lol). Further, the 1 to 5 numerical value of the mat file was set by me. (If it would help).

Thanks

Ferd

Answer 1

[Jan]

See: FAQ: How to process a sequence of files.

list = dir('A_*.mat');
Data = cell(1, length(list));
for k = 1:length(list)
  matFilename = list(k).name;
  matData = load(matFilename);
  Data{k} = matData.A;
  % Or if the file A_1 contains the matrix A_1:
  %   [dummy, name] = fileparts(matFilename);
  %   Data{k} = matData.(name);
  % Or:
  %   Data{k} = matData.(sprintf('A_%d', k));
end

Be sure to read this also: FAQ: How can I create A1, A2, ... and consider the recommendation to avoid hiding an index in the name of a variable.

[Ferd]

Hey Simon, thanks man. The logic works!

The A_1 to A_5 are basically different Runs. For convinience I set it up as the type of Run(the alphabet- same Run) and when it was conducted(the number) Hence, the A's and numbers. Yea, just wanted to plot the results for each Run that have the same parameters.

Thanks Ferd