function [] = plotBarStackGroups(stackData, groupLabels)
%% Plot a set of stacked bars, but group them according to labels provided.
%%
%% Params:
%% stackData is a 3D matrix (i.e., stackData(i, j, k) => (Group, Stack, StackElement))
%% groupLabels is a CELL type (i.e., { 'a', 1 , 20, 'because' };)
%%
%% Copyright 2011 Evan Bollig (bollig at scs DOT fsu ANOTHERDOT edu
%%
%%
NumGroupsPerAxis = size(stackData, 1);
NumStacksPerGroup = size(stackData, 2);
% Count off the number of bins
groupBins = 1:NumGroupsPerAxis;
MaxGroupWidth = 0.65; % Fraction of 1. If 1, then we have all bars in groups touching
groupOffset = MaxGroupWidth/NumStacksPerGroup;
figure
hold on;
for i=1:NumStacksPerGroup
Y = squeeze(stackData(:,i,:));
% Center the bars:
internalPosCount = i - ((NumStacksPerGroup+1) / 2);
% Offset the group draw positions:
groupDrawPos = (internalPosCount)* groupOffset + groupBins;