Display pairs of random images from a file

Hi,

I am new to MATLAB, so I don't know exactly how to get it to do what I want.

Right now, I have a script that just randomly displays an image file from a directory. I want to change this so it randomly displays two images from that directory ... however, I want to do so in a way that every possible pairing of images will be given exactly once. So, if the pictures are:

frog cat dog mouse house

I want to get:

frog - cat frog - dog frog - mouse frog - house cat - dog cat - mouse cat - house dog - mouse dog - house mouse - house

What is the easiest way to go about doing this? Originally I was going to simply create new picture files such that each one already contains the two images I want side by side. However, there are a large number of possible pairings so it will be too time consuming to do this.

How do I do this?

(Here is my script as it is, which I know doesn't do what I want it to do:

dfiles = d(~[d.isdir]);

genRandNum = randperm(length(dfiles));

filename = dfiles(genRandNum(i)).name;

imageName = fullfile('Desktop', 'SEMREL', 'Pictures', filename);

imshow(imageName, 'Parent');

Answer 1

[David Young]

Something based on this should work (not tested):

dfiles = d(~[d.isdir]);
N = length(dfiles);
genRandNum = randperm(N^2);
for i = 1:N^2;
  [n1, n2] = ind2sub(N, genRandNum(i));
  if n1 < n2
    filename1 = dfiles(n1).name;
    imageName1 = fullfile('Desktop', 'SEMREL', 'Pictures', filename1);
    filename2 = dfiles(n2).name;
    imageName2 = fullfile('Desktop', 'SEMREL', 'Pictures', filename2);
    image1 = imread(imagename1);
    image2 = imread(imagename2);
    subplot(1,2,1); imshow(image1);
    subplot(1,2,2); imshow(image2);
    pause;
  end
end

[Ryan]

Thanks!