Error in sub plot when I resize Image to divide it to blocks ,can any one solve it?

I use this code from math works but I change the new size of resizing function and I get this error

clc;    % Clear the command window.
format compact;
workspace;  % Make sure the workspace panel is showing.
fontSize = 20;
% Read in a standard MATLAB color demo image.
folder = fullfile(matlabroot, '\toolbox\images\imdemos');
baseFileName = 'peppers.png';
fullFileName = fullfile(folder, baseFileName);
% Get the full filename, with path prepended.
fullFileName = fullfile(folder, baseFileName);
if ~exist(fullFileName, 'file')
  % Didn't find it there.  Check the search path for it.
  fullFileName = baseFileName; % No path this time.
  if ~exist(fullFileName, 'file')
    % Still didn't find it.  Alert user.
    errorMessage = sprintf('Error: %s does not exist.', fullFileName);
    uiwait(warndlg(errorMessage));
    return;
  end
end
rgbImage = imread(fullFileName);
% For demo purposes, let's resize it to be 64 by 64;
rgbImage = imresize(rgbImage, [512 512]);
% Get the dimensions of the image.  numberOfColorBands should be = 3.
[rows columns numberOfColorBands] = size(rgbImage)
ca = mat2cell(rgbImage,8*ones(1,size(rgbImage,1)/8),8*ones(1,size(rgbImage,2)/8),3);
plotIndex = 1;
for c = 1 : size(ca, 2)
  for r = 1 : size(ca, 1)
    fprintf('c=%d, r=%d\n', c, r);
    subplot(256,256,plotIndex);
        x=ca{r,c};
        size(x)
    imshow(x);

    plotIndex = plotIndex + 1
  end
end
% Enlarge figure to full screen.
set(gcf, 'units','normalized','outerposition',[0 0 1 1]);

The original resizing was to 64*64

Answer 1

[Image Analyst]

It worked for me, other than being real slow. What was the error message you got? By the way, change

subplot(256,256,plotIndex);

to

subplot(64, 64, plotIndex);

and put a drawnow after the r loop, just before the end of the c loop.

[Ameligege]

what do you mean by"put a drawnow after the r loop, just before the end of the c loop." ?

[Ameligege]

The Error was in subplot ,but now I am trying this code after your solution but it does not show the output? Because I want to see the blocks of the same size 8*8