***R2014b Compatibility Note: Mouse interaction is enabled but the backpanel is not yet supported.***

FCOLORBAR by default behaves identical to the built-in colorbar function, appending a fixed colorbar to the current axes in the default (right) location. When the colorbar is floating inside the axes (either by LOCATION argument or via the colorbar's context menu) a background panel appears to aid visibility of the colorbar axes labels. Moreover, the colorbar inside the axes can be grabbed using mouse and repositioned anywhere on the figure.

Pre-R2014b Example (adding colorbar to a Signal Processing Toolbox's spectrogram example):

t=0:0.001:2; % 2 secs @ 1kHz sample rate
y=chirp(t,100,1,200,'q'); % Start @ 100Hz, cross 200Hz at t=1sec
spectrogram(y,128,120,128,1E3); % Display the spectrogram
title('Quadratic Chirp: start at 100Hz and cross 200Hz at t=1sec');

cb = fcolorbar('east','FontSize',8); % 'east' -> inside axes colorbar display
ylabel(cb,'Power (dB)') % backpanel widens automatically to be under the ylabel
set(cb,'Position',[0.85 0.14 0.03 0.5]) % background panel automatically follows the colorbar