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Simple question regarding bar plot with categorical data

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maho
maho on 6 Oct 2017
Edited: Souarv De on 8 Apr 2021
Hello guys,
I am new to matlab, and I'm trying to do a simple bar plot, like this:
x = ["bananas" "apples" "cherries"];
y = [14,12,7];
bar(categorical(x),y);
The problem is that bar() function seems to sort the x-labels in alphabetical order. Is there any way to override this behaviour, so that the x-labels are left in their original order?

Accepted Answer

Sean de Wolski
Sean de Wolski on 6 Oct 2017
Edited: Sean de Wolski on 6 Oct 2017
x = categorical(["bananas" "apples" "cherries"]);
x = reordercats(x,{'bananas' 'apples' 'cherries'});
y = [14,12,7];
bar(x,y);
Categoricals can have order associated with them (for the purpose of relational operators).
  5 Comments
tesarj13
tesarj13 on 23 Nov 2020
Even better with coversion to string:
x = categorical(["bananas" "apples" "cherries"]);
x = reordercats(x,string(x));
y = [14,12,7];
bar(x,y);

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More Answers (3)

Souarv De
Souarv De on 8 Apr 2021
Edited: Souarv De on 8 Apr 2021
I also faced the same issue. There are numerous shortcut techniques available to solve it out. What I used to follow is as below :
x = categorical(["bananas" "apples" "cherries"]);
x = reordercats(x,cellstr(x)');
y = [14,12,7];
bar(x,y);

Rik
Rik on 6 Oct 2017
Edited: Rik on 6 Oct 2017
The problem is not in bar, but in categorical. I can't find in the doc how to preserve order (with unique I know there is a switch to do so). So my suggestion would be to convert it yourself:
[~,ia,~]=unique(x,'stable');
x2=1:length(x);
x2=x(ia);
bar(x2,y)
xticks(x2)
xticklabels(x)%might not work, as this expects a cell stray containing strings
Of course, your labels are very likely to be unique, otherwise bar wil most likely yield an error, so this should work the same in all valid situations:
x2=1:length(x);
bar(x2,y)
xticks(x2)
xticklabels(x)%might not work, as this expects a cell stray containing strings
  2 Comments
maho
maho on 9 Oct 2017
Thank you for your response, Rik!
Your solution works, but it doesn't produce the same graphical output as using bar() with a categorical 'x' variable. In particular, if you squash the graph window horizontally, so that it is tall and narrow, you see that:
bar() using categorical variables very cleverly rotates the labels so they don't mush together
bar() using xticklabels() not so cleverly mushes the labels together so they become unreadable. :(
The same thing happens if you have many columns in your bar chart in relation to the physical width of your graph.

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Steven Lord
Steven Lord on 6 Oct 2017
If you're using release R2016b or later you could use histogram with a vector of BinCounts instead of using bar.
x = ["bananas" "apples" "cherries"];
C = categorical(x);
y = [14,12,7];
h = histogram('Categories', C, 'BinCounts', y);

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