# add standard deviation value and text on bars

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talayeh ghodsi on 28 Nov 2020
Commented: Star Strider on 30 Nov 2020
hi every body
I have three tipe of values and i have plot the bar of mean values. now i wnat to show the value of standard deviation to it (as in https://www.mathworks.com/help/matlab/creating_plots/bar-chart-with-error-bars.html) and also add the value text to the mean on the top of bars
Y=[0.9 0.83 0.700;1.586 1.604 1.989] %% mean values
STD_low=[0.0569,0.05499,0.0438;0.27 0.058 0.164] %% standard deviations
STD_high=STD_low;
b=bar(X,Y)
xtips1 = b(1).XEndPoints;
ytips1 = b(1).YEndPoints;
labels1 = string(b(1).YData);
text(xtips1,ytips1,labels1,'HorizontalAlignment','center',...
'VerticalAlignment','bottom')
xtips2 = b(2).XEndPoints;
ytips2 = b(2).YEndPoints;
labels2 = string(b(2).YData);
text(xtips2,ytips2,labels2,'HorizontalAlignment','center',...
'VerticalAlignment','bottom')
xticklabels(X)
could anyone help me with that please?

Rik on 28 Nov 2020
You seem to already know how to use the relevant functions. Your code is not formatted properly, so it is a bit harder to read than it needs to be. It looks like you are attempting to use numbered variables to process every bar. Why not use a loop?
talayeh ghodsi on 28 Nov 2020
as my image attached, i need to add the Standard deviation to the bars
I dont know how to use loop to solve the problem

Star Strider on 28 Nov 2020
Edited: Star Strider on 28 Nov 2020
When I try to run your code, I get:
Unrecognized function or variable 'X'.
In its absence, try this:
Y=[0.9 0.83 0.700;1.586 1.604 1.989]; %% mean values
X = 1:size(Y,2); % Substitute For Missing 'X’
STD_low=[0.0569,0.05499,0.0438;0.27 0.058 0.164]; %% standard deviations
STD_high=STD_low;
figure
b=bar(X,Y); % Return ‘bar’ Handle
xtips1 = b(1).XEndPoints;
ytips1 = b(1).YEndPoints;
for k1 = 1:size(Y,1)
ctr(k1,:) = bsxfun(@plus, b(k1).XData, b(k1).XOffset'); % Note: ‘XOffset’ Is An Undocumented Feature, This Selects The ‘bar’ Centres
ydt(k1,:) = b(k1).YData; % Individual Bar Heights
end
hold on
errorbar(ctr, ydt, STD_low, '|g') % Plot Error Bars (Note: ‘|’ Is New With R21020b, Use ‘.’ Otherwise)
labels1 = string(b(1).YData);
text(xtips1,ytips1,labels1,'HorizontalAlignment','center',...
'VerticalAlignment','bottom')
xtips2 = b(2).XEndPoints;
ytips2 = b(2).YEndPoints;
labels2 = string(b(2).YData);
text(xtips2,ytips2,labels2,'HorizontalAlignment','center',...
'VerticalAlignment','bottom')
xticklabels(X)
EDIT — (28 Nov 2020 at 15:24)
.

Star Strider on 30 Nov 2020
The missing ‘X’ is the reason you are having problems using my code with it. It is not possible to use this code with categorical variables, because categorical values are not numeric, so it is not possible to calculate with them.
Change it to:
Y=[0.884 1.586;0.901 1.801;0.697 1.404]; %% mean values
X = categorical({'GT','whole V.','Proposed method'});
X = reordercats(X,{'GT','whole V.','Proposed method'});
Xv = 1:numel(X); % Use Numerical Values Of ‘X’ To Plot Error Bars
STD_low=[0.0125 0.27;0.024 0.0124 ;0.051 0.0584]; %% standard deviations
STD_high=STD_low;
figure
b=bar(Xv,Y); % Return ‘bar’ Handle
xtips1 = b(1).XEndPoints;
ytips1 = b(1).YEndPoints;
for k1 = 1:size(Y,2)
ctr(k1,:) = bsxfun(@plus, b(k1).XData, b(k1).XOffset'); % Note: ‘XOffset’ Is An Undocumented Feature, This Selects The ‘bar’ Centres
ydt(k1,:) = b(k1).YData; % Individual Bar Heights
end
hold on
heb = errorbar(ctr, ydt, STD_low.', STD_high.', '.g'); % Plot Error Bars (Note: ‘|’ Is New With R21020b, Use ‘.’ Otherwise)
for k = 1:numel(heb)
heb(k).MarkerSize = 1;
end
labels1 = string(b(1).YData);
text(xtips1,ytips1,labels1,'HorizontalAlignment','center',...
'VerticalAlignment','bottom')
xtips2 = b(2).XEndPoints;
ytips2 = b(2).YEndPoints;
labels2 = string(b(2).YData);
text(xtips2,ytips2,labels2,'HorizontalAlignment','center',...
'VerticalAlignment','bottom')
xticklabels(X)
This works with your categorical ‘X’. (I made a few other improvements as well.)
Star Strider on 30 Nov 2020
talayeh ghodsi wrote —
Star Strider on 30 Nov 2020
My pleasure!