the cyclist-
I ran into this same problem when switching from Matlab 2011b to 2015b, with the updated graphics engine. After fooling around for a bit, I found that the following code will work (adapted from your original post):
%
mean_velocity = [5 6 7; 8 9 10]; % mean velocity
std_velocity = randn(2,3); % standard deviation of velocity
figure
hold on
hb = bar(1:3,mean_velocity');
% For each set of bars, find the centers of the bars, and write error bars
pause(0.1); %pause allows the figure to be created
for ib = 1:numel(hb)
%XData property is the tick labels/group centers; XOffset is the offset
%of each distinct group
xData = hb(ib).XData+hb(ib).XOffset;
errorbar(xData,mean_velocity(ib,:),std_velocity(ib,:),'k.')
end
I'm not quite sure why the pause is required- it seems that the new graphics engine requires a little bit of time before it will recognize the figure handle properly. I've tried it in other scripts where there is more code in between the plotting and the additional math and it seems to work fine, as well as trying it just via command line, and found the same issue. This should work in any version r2014b+.
