How to add a colormap manually as x-axis under an histogram?

Dear all,

I have created an histogram to look at the distribution of pixels per grey in an (8-bit) image. The reason for not using the imhist function is because I create an histogram with a double y-axis, one on the left (a log-axis) and one on the right (normal axis) to represent how wide the distribution is at the low values. (The function I use is attached, in case it is of interest to anyone. It is just an adaptation done quickly from a function by Araja.) The type of histogram I get is this:

I would like to add a colormap under the x-axis, like the one we can see here:

Anybody knows how to do so?

Thank you in advance!

Answer 1

[Steven Lord]

Call colorbar with the 'southoutside' location as shown in the "Add Horizontal Colorbar to Graph" example on the documentation page.

Answer 2

[darova]

Use colorbar

contourf(peaks(60))
colormap cool
colorbar('location','southoutside')

Answer 3

[Olfa Lopez]

Here is how I managed to make the colorbar take the space of the x-axis, if it can help someone someday:

original_axes_pos = get(hAx2,'Position');
colormap gray
colorbar('location','southoutside',...
         'Ticks',[],...
         'TickLabels',{''})
set(hAx2,'Position',original_axes_pos);

[Roger Breton]

Thanks!