multi bar labeling plot

I want to label each three bars as p1, p2 and p3 for all at the base as the pic attached.. i appreciate any help someone can provide.

[Adam Danz]

Wouldn't a legend defining the colors make more sense?

[Ali Ali]

you are right.. but i'll manopolate with the colors later.. so it will not be fixed as it now.

Answer 1

[Adam Danz]

Here's how to locate the center of each grouped bar and label them.

Starting in Matlab R2019B, the center of each bar is stored in

h = bar(___);

h.XEndPoints % x centers

h.YEndPoints % y endpoints

Prior to Matlab R2019B, you can use an undocumented property "XOffset". This was developed and tested in r2019a.

xCnt are the bar centers.

% Generate grouped bar plot
figure()
v = randi(20,12,3); 
h = bar(v,.8); 

% Get group centers
xCnt = get(h(1),'XData') + cell2mat(get(h,'XOffset')); % XOffset is undocumented!
% Create Tick Labels
xLab = repmat({'p1','p2','p3'},1,numel(xCnt)/3); 
% Set individual ticks
set(gca, 'XTick', sort(xCnt(:)), 'XTickLabel', xLab)

Alternatively, you could rotate the x tick labels

set(gca, 'XTick', sort(xCnt(:)), 'XTickLabel', xLab, 'xticklabelrotation', 90)
% Or use xtickangle():  https://www.mathworks.com/help/matlab/ref/xtickangle.html

The best solution would be to use a legend

legend(h,{'p1','p2','p3'})

[Sulaymon Eshkabilov]

My understanding of the problem was just to set colors on each bar that is all. If this is the case, then you need to fix a color in your bar charts as shown above. Otherwise, all done = well, already!

[Ali Ali]

Adam Danz this is just perfect bro.

[Adam Danz]

Glad I could help. I recommend writing a comment in your code noting that xoffset is an undocumented property in case it's ever removed in the future.

[Ali Ali]

thank you for this notiation Adam.. I have another question about the possiblility of making the labels at the base mix of p1,p2,p3 and the iterations numbers..?

[Adam Danz]

Is the iterations number the group number? Something like this below?

p1 i1
p2 i1
p3 i1

p1 i2
p2 i2
p3 i2

If so, give this a shot.

% Create Tick Labels
xLab = repmat({'p1 i','p2 i','p3 i'},1,numel(xCnt)/3); 
xLab = strrep(xLab,'i',strsplit(num2str(repelem(1:size(v,1),1,size(v,2))))); 

[Ali Ali]

like below if you can Adam

[Adam Danz]

% xLab are the labels for each individual bar.  The pattern you want is the following:
% for every odd triplet, you want [nothing, #, nothing] 
% and for every even triplet you want [p#, p#, p#]. 
% We already have the p# labels so we just need to alter the odd number groups. 
% Step 1) Identify the odd number groups. 
isOdd = repmat(logical([1,1,1,0,0,0]),1,length(xLab)/6);
% Step 2) Create new labels
newLabs = strsplit(sprintf('| |%d| |', 1:2:length(xLab)/3),'|'); 
newLabs(cellfun(@isempty, newLabs)) = []; 
% Step 3) replace the p# labels for odd groups with [nothing, #, nothing]
xLab(isOdd) = newLabs; 
% Step 4) assing newlabels to plot
set(gca, 'XTick', sort(xCnt(:)), 'XTickLabel', xLab, 'xticklabelrotation', 90)

[Ali Ali]

thank you a lot Adam.. this is realy helped me.

Answer 2

[Sulaymon Eshkabilov]

Hi Ali,

Here is a simple solution to your problem:

A= randi([15, 25], 13, 3); % Insert your data here

H = bar(A); shg
H(1).FaceColor='g'; 
H(2).FaceColor='r';
H(3).FaceColor='b';

Good luck.

[Ali Ali]

Sulaymon Eshkabilov i think you did not get my point.. anyway thank you for your help.

Answer 3

[Sergio Yanez-Pagans]

I would suggest trying this:

https://www.mathworks.com/matlabcentral/fileexchange/97964-linemarks

[Adam Danz]

Cool function, but how does that address the question of how to label the bar groups?