How to keep the order in plotting scatter plot with categorical variables
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Hi,
I am using scatter (b,a) where a is categorical variable and b is double. The plot shows a different order than in my list in a. How do I keep the same order in the plot?
1 Comment
KALYAN ACHARJYA
on 5 Jun 2018
Share the expected plot figure (idea)? What are you getting now?
Answers (2)
KSSV
on 5 Jun 2018
0 votes
Have a look on gscatter
M_A_C
on 12 Aug 2024
0 votes
Hello Chung,
Here is a solution from my painful own experience:
If a (generally x-axis) is categorical, you should fix its order first.
For example, my categorical column has the following values: BL01-3s-3r MP01-3s-3r MPAP00W01-3s-3r MPAP00W02-3s-3r MPAP00W03-3s-3r MPAP00W04-3s-3r MPAP00W05-3s-3r MPAP00W06-3s-3r MPAP05W07-3s-3r MPAP10W08-3s-3r MPAP15W09-3s-3r MPAP20W10-3s-3r BL02-3s-3r. scatter function reorders the data in alphabetical order and moves BL02-3s-3r to the second place. See plot below:

I solved it creating a : valueset = {'BL01-3s-3r','MP01-3s-3r','MPAP00W01-3s-3r','MPAP00W02-3s-3r','MPAP00W03-3s-3r','MPAP00W04-3s-3r','MPAP00W05-3s-3r','MPAP00W06-3s-3r','MPAP05W07-3s-3r','MPAP10W08-3s-3r','MPAP15W09-3s-3r','MPAP20W10-3s-3r','BL02-3s-3r'};
then T.Channel1_E1E2 = categorical(T.Channel1_E1E2,valueset,'Ordinal',true); I use table istead. See plot below:

NOTE: If you use gscatter as KSSV recommends, you end up getting an error message like this one:
Error using gscatter
The value of 'x' is invalid. It must satisfy the function:
@(x)isnumeric(x)||isdatetime(x)||isduration(x)||iscalendarduration(x)||iscategorical(x).
Hope this help.
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