How to change the color for bar graphs and create space between grouped bars?

Hi How to change the face color of the individual bar in a grouped bar chart. How to create space between different groups in a bar chart.

For example, as shown in the below image. I have 3 different category i.e. A,B,C and each category has 5 bars i.e. 2,5,10 20 and 25. How to create this kind of graph in matlab.

The data for A, B, C are... A= [10,13,9,6,20]' B= [2, 4, 7, 9,10]' C=[-2,-3,-8,-10,-11]'

Thanks

Answer 1

[dpb]

ABC=[ [10,13,9,6,20]' [2, 4, 7, 9,10]' [-2,-3,-8,-10,-11]'].';
hBar=bar(ABC,'grouped');      % basic grouped bar plot, keep handle
hFg=gcf; hAx=gca;             % handles to current figure, axes
ylim([-20 30])                % space out a little extra room
hAx.XTickLabel={'A';'B';'C'}; % label x axis
hAx.YColor=get(hFg,'color'); box off  % hide y axis/labels, outline
hLg=legend(num2str([2;5;10;20;25]), ...
           'orientation','horizontal', ...
           'location','north'); legend('boxoff') % add legend

yields

With more recent release than I have here (R2014b) you can also move the y-axis to the origin with

hAx.XAxisLocation='origin';

to essentially duplicate the example.

hBar(N).FaceColor='r';

would for example color the N th bar in the group red if don't like default colors (which, granted, aren't the most pleasing they could be).

ADDENDUM: OK, am back so to do error bars on the bar plot--

Start by combining the data into an array instead of using separate variables -- a general coding principle in Matlab, btw, makes things much more efficient as a rule.

ABCerr=[A_error;B_error;C_error];
x=repmat([1:size(ABC,1)].',1,size(ABC,2));  % bar x nominals
xOff=bsxfun(@plus,x,[hBar.XOffset]); % bar midpoints x
hold all                             % keep axis limits, etc.
hEB=errorbar(xOff,ABC,ABCerr,'.');   % add errorbars

Above will have a set of default colors for the errorbar series that won't necessarily coincide with the bar series already have.

I do not know where the default bar color series values are stored; the default 'FaceColor' value is the string 'Flat' which isn't of much help in matching to but as noted above you can reset it to either one of the eight defined color strings or any RGB triplet to match up with the default errorbar colors could be

for i=1:length(hBar)
  hBar(i).FaceColor=hEB(i).Color;
end

or choose a set for both. Or, on further reflection and looking at the plot created, maybe 'k' for all the error bars might help them be visible, particularly the lower limits that are in the bars.

Another fixup would be

hBar(1).BaseLine.Color='k';

to show the baseline under the bars; it follows the y-axis color by default so became invisible when turned that color to match the figure background.

[dpb]

[Moved OP's Answer to comment -- dpb]

Thanks, its perfect.

When I moved the X-axis to origin, the label 'C' is mixing with bars. Is it possible to keep the 'C' inside the bar chart? then it will be same as 'A' and 'B'.

Could you please tell me, how to give error bars. I have the following data for errors.

A_error= [2.74 3.67 4.71 4.08 2.37]
B_error= [2.97 1.65 3.37 1.69 5.95]
C_error= [1.26 2.32 3.53 2.28 3.69]

Thanks

[dpb]

"... Is it possible to keep the 'C' inside the bar chart?"

I thought it was perfect! {VBG} :)

Not with the axis object, no. You'll note your original is the same way. You could use text and write the axis labels where you want them.

You can overlay an errorbar plot on top of bar but it takes a little more than I've got time to do right now.

I think there's a FEX submittal but not positive.

As hint, there's a hidden property .XOffset in the bar handle properties that gives the offset from the nominal x to the center of each bar. Retrieve and use that to set the error bar positions if use errorbar

I'd give example but I'm already late for an appointment in town...

[dpb]

Again move Answer to Comment...dpb

Hi

How to turn those vertical bar graphs into horizontal bars keeping the same structure (same code as your first comment.

Thanks

[dpb]

For horizontal bar graph, use barh

Prior to release after R2014b (but undocumented as to when except perhaps in individual release notes) errorbar only supported vertical error bars; at some point w/ HG2 it added a new 'orientation' property.

Same ideas hold as before; simply swap the axes looking at for the specific properties as needed...

Answer 2

[R7 DR]

Hi Thanks. Now its perfect :) :)

I still have one question. I am trying to give hatching lines in place of colors using the following file, but the quality of the image is very bad. http://se.mathworks.com/matlabcentral/fileexchange/26797-applyhatch-plusc

Could you please tell me how to give differnt hatching pattern on bar chart?

Thanks

[dpb]

Another Matlab weakpoint -- there's no explaining TMW's failure to include multitude of hatching patterns in lo! these many years.

I've also tried a number of FEX hatching submissions and had only marginal success with any of them, sorry.

The ones I've used worked (to a lesser or greater degree of pleasing success) directly on patch object handles; I don't know about trying them with bar series objects.

In short, I don't know enough specifically to help; I'd suggest it's a big enough oversight to be worth a bug/feature report and enhancement request. I don't recall if I actually submitted one back when was playing with those routines or not; that was a couple years ago now...

Answer 3

[Hunter Pruett]

Just finished the barmod function--controls relative position of just about everything in the plot. Hope this helps anyone else with this question--I was having similar issues and found the lack of functionality a bit disappointing. See the demo for color modification and such.

https://www.mathworks.com/matlabcentral/fileexchange/75853-barmod