How to control the margin size around subplots? - matlab

Question

I'm plotting 5 x 3 plots using subplot command, but there are massive margins around each subplot.
How do I control the margin size around them?
figure;
for c=1:15
subplot(5,3,c);
imagesc(reshape(image(:,c), 360,480));
colormap gray;
axis image;
end

Answer 1

The problem is that Matlab assigns the position property of each axis such that there is space around each plot. You can either adjust the position property, or you can get subaxis from the File Exchange and set up the subplots the way you like.

Answer 2

Take a look at the axes's LooseInset and OuterPosition properties:
http://undocumentedmatlab.com/blog/axes-looseinset-property/

Answer 3

Since MATLAB R2019b you can use tiledlayout function to control the spacing of the subplots.
Here's an example which shows how to obtain subplots without tile spacing:
figure
example_image = imread('cameraman.tif');
t = tiledlayout(5,3);
nexttile
for c= 1:15
imagesc(example_image(:,c))
if c < 15
nexttile
end
end
t.TileSpacing = 'None';

Answer 4

In addition to the other answers, you could try Chad Greene's smplot from the FileExchange. This will produce a 'small multiple' plot and automatically deal with some of the hassle of Matlab's position property.
Example below showing default subplot behaviour, smplot with axis off and smplot with axis on, respectively:
image = randn(360*480,15);
% default subplot
figure;
for c=1:15
subplot(5,3,c);
imagesc(reshape(image(:,c), 360,480));
colormap gray;
axis image;
end
% smplot axis off
figure;
for c=1:15
smplot(5,3,c);
imagesc(reshape(image(:,c), 360,480));
colormap gray;
axis off;
end
% smplot axis on
figure;
for c=1:15
smplot(5,3,c,'axis','on');
imagesc(reshape(image(:,c), 360,480));
colormap gray;
axis tight;
end

Answer 5

To minimize the white space surrounding each subplot, run: [1]
for c=1:15
h_ax = subplot(5,3,c);
% [...]
outerpos = get(h_ax,'OuterPosition');
ti = get(h_ax,'TightInset');
left = outerpos(1) + ti(1);
bottom = outerpos(2) + ti(2);
ax_width = outerpos(3) - ti(1) - ti(3);
ax_height = outerpos(4) - ti(2) - ti(4);
set(h_ax,'Position',[left bottom ax_width ax_height]);
end
This implementation automates the principle outlined in Jonas's answer.
[1] https://www.mathworks.com/help/releases/R2015b/matlab/creating_plots/save-figure-with-minimal-white-space.html