MATLAB Answers

0

Avoid colorbar resizing image

Asked by Jason on 2 Mar 2012
Latest activity Answered by Sindar
on 27 Mar 2019
Hi guys -
How can I prevent an image from being resized when a colorbar is introduced? I am plotting two plots side by side, one with a line plot and one with imagesc. Before the colorbar is added the plots are exactly the same size, which I would prefer, but when I add the colorbar the imagesc plot is resized to be smaller than before. I'd like to avoid this.

  0 Comments

Sign in to comment.

4 Answers

Answer by Image Analyst
on 2 Mar 2012
 Accepted Answer

Jason, just try this demo code and I think all your questions will be answered:
clc; % Clear the command window.
close all; % Close all figures (except those of imtool.)
workspace; % Make sure the workspace panel is showing.
fontSize = 20;
format compact;
% Put up a plot in the first position
h1 = subplot(1,2,1);
plot(rand(15), 'LineWidth', 3);
title('Line Plot', 'FontSize', fontSize);
% Get the current axis size
originalSize1 = get(gca, 'Position')
% Put up an image in the second position
% Read in a standard MATLAB gray scale demo image.
folder = fullfile(matlabroot, '\toolbox\images\imdemos');
baseFileName = 'cameraman.tif';
% Get the full filename, with path prepended.
fullFileName = fullfile(folder, baseFileName);
grayImage = imread(fullFileName);
% Display the original gray scale image.
h2 = subplot(1, 2, 2);
imshow(grayImage, []);
title('Original Grayscale Image', 'FontSize', fontSize);
% Enlarge figure to full screen.
set(gcf, 'units','normalized','outerposition',[0 0 1 1]); % Maximize figure.
set(gcf,'name','Demo by ImageAnalyst','numbertitle','off');
% Get the current axis size
originalSize2 = get(gca, 'Position')
uiwait(msgbox('Click OK to see a colorbar and watch how it changes both axes sizes'));
colormap('winter');
colorbar;
title('Shrunken Image with ColorBar', 'FontSize', fontSize);
% Print out the new sizes and see how they are different.
newSize1 = get(h1, 'Position')
newSize2 = get(h2, 'Position')
uiwait(msgbox('Click OK to restore the original image size'));
% Reset axes to original size.
set(h1, 'Position', originalSize1); % Can also use gca instead of h1 if h1 is still active.
set(h2, 'Position', originalSize2); % Can also use gca instead of h2 if h2 is still active.
title('Restored Image with ColorBar', 'FontSize', fontSize);
% Print out the restored sizes to verify.
restoredSize1 = get(h1, 'Position')
restoredSize2 = get(h2, 'Position')

  3 Comments

Jason on 2 Mar 2012
That's a helpful demo, Image Analyst! I can see how I might change my code to keep the image plot from being resized by the colorbar.
As an additional request, I posted another question in which I mentioned that when I make a subplot figure like this, formatted in exactly the same way you did it, that a title that is supposed to be printed above both figures and centered is erased. Can you edit the example above to include a title in the figure above the individual title figures?
Image Analyst
on 3 Mar 2012
You mean like suplabel?: http://www.mathworks.com/matlabcentral/fileexchange/7772-suplabel
Jason on 5 Mar 2012
Yep, that's exactly what I mean. I'll try that!

Sign in to comment.


Answer by Sindar
on 27 Mar 2019

If you set the position of the colorbar manually, the figure won't be resized. So:
cb=colorbar;
cb.Position = cb.Position + 1e-10; % or + [left, bottom, width, height] to place it where you want
Will auto-place the colorbar, then un-resize the plot.

  0 Comments

Sign in to comment.


Answer by Chad Greene
on 2 Mar 2012

This is sort of a clunky solution, but you can force the entire figure to be the size you want by putting this line after plotting:
set(gcf,'position',[100 100 1100 650]) % sets figure size
I believe the 100s above correspond to the position (in pixels) of the lower left corner of the figure on your screen, and 1100 and 650 are the figure width and height, respectively.

  3 Comments

Jason on 2 Mar 2012
Hmm, thanks Chad, I'll see if that helps.
Jason on 2 Mar 2012
Not sure what's going on, but the addition of the line you suggested makes the figure disappear completely! I used if to point to the handle of the parent figure, and the figure simply disappeared. Super weird!
Chad Greene
on 2 Mar 2012
It's possible that my line placed your figure somewhere off your screen. Try running your code WITHOUT my line, then in the command line type
get(gcf,'position')
It should return some value like [50 100 500 450] (I'm making up the values). Those are the default values for the position and size of your figure. If you want your figure to be, say, 100 pixels wider, then take those values and type in
set(gcf,'position',[50 100 600 450])

Sign in to comment.


Answer by Jason on 2 Mar 2012

For clarification, here is the code loop I use to generate i figures of 2 plots each:
for i = 1:plotPCnum
I = num2str(i);
h = figure('Units','normalized');
titlestr = char(['Scores and loadings for PC ',I]);
title(titlestr); set(gca,'Visible','off');
set(get(gca,'Title'),'Visible','on');
axes('OuterPosition',[0 0 .5 1],...
'ActivePositionProperty','outerposition');
%subplot(1,2,1); ...
box('on'); hold('all'); plot(loads_wt(:,i));
axis square; axis tight;
title(['Loadings PC ',num2str(I)]);
%subplot(1,2,2);
scores = axes('OuterPosition',[.4 0 .5 1]);
imagesc(reshape(scores_wt(:,i), [nrows ncols]));...
axis image; axis square;
set(scores,'XTick', [], 'YTick', []);
title(['Scores PC ',num2str(I)]);
colormap('jet');
colorbar
saveas(h,titlestr,'fig');
logline = char([titlestr,' has been created.']);
fprintf(fidOUT,'%s\n',logline);
end

  0 Comments

Sign in to comment.