Error using subplot (line 301) Index exceeds number of subplots.

hi, guys..

i want to get the sub image of a gray scale image size 3081x4137. can i just do directly it by running the code that i saw in matlab ? fyi, i'm new to the matlab so i just try to run some code that has been created by some programmers in matlab to understand it.

actually i have tried it and i get error in 'sublot (2,2,sliceNumber)' when i run it in here :

 for row = 1 : blockSizeR : rows
 for col = 1 : blockSizeC : columns

        row1 = row;
        row2 = row1 + blockSizeR - 1;
        row2 = min(rows, row2); % Don't let it go outside the image.
        col1 = col;
        col2 = col1 + blockSizeC - 1;
        col2 = min(columns, col2); % Don't let it go outside the image.
        % Extract out the block into a single subimage.
        oneBlock = b(row1:row2, col1:col2);
        % Specify the location for display of the image.
        subplot(2, 2, sliceNumber);
        imshow(oneBlock);
        % Make the caption the block number.
        caption = sprintf('Block #%d of 5', sliceNumber);
        title(caption, 'FontSize', fontSize);
        drawnow;*

what should i do, please ?

Answer 1

[Walter Roberson]

 rowblocks = 1 : blockSizeR : rows;
 colblocks = 1 : blockSizeC : columns;
 numrowblocks = length(rowblocks);
 numcolblocks = length(colblocks);
 for rowidx = 1 : numrowblocks
   row = rowblocks(rowidx);
   for colidx = 1 : numcolblocks
       col = colblocks(colidx);

        row1 = row;
        row2 = row1 + blockSizeR - 1;
        row2 = min(rows, row2); % Don't let it go outside the image.
        col1 = col;
        col2 = col1 + blockSizeC - 1;
        col2 = min(columns, col2); % Don't let it go outside the image.
        % Extract out the block into a single subimage.
        oneBlock = b(row1:row2, col1:col2);
        % Specify the location for display of the image.
        subplot(numrowblocks, numcolblocks, sliceNumber);
        imshow(oneBlock);
        % Make the caption the block number.
        caption = sprintf('Block #%d of 5', sliceNumber);
        title(caption, 'FontSize', fontSize);
        drawnow;
    end
 end

However, I recommend you consider https://www.mathworks.com/matlabcentral/fileexchange/35085-mat2tiles--divide-array-into-equal-sized-sub-arrays

[Ade Aulya]

thank you so much :)