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Return rows from a table with a unique combination of categories

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Hello,
I have a large table [2166094x9 table] (sample variable attached) and I would like to get the rows from the table that have a unique combination of 6 categorical variables. Location1 and Location2 have combinations that repeatad (e.g., Location1 = LVL1 , Location2 = RV1 represents a duplicate row as Location1 = RV1 Location2 = LVL1) This is what I have, but I can't seem to make it work.
Thank you for time and consideration.
X=[Data.Subnum, Data.Tp, Data.Location1, Data.Location2, Data.Cond, Data.Freq];
j=findgroups(X);
[idx,idy]=unique(j,'stable');
HCUniqueAll=Data(idy,:);
summary(HCUniqueAll)
  1 Comment
dpb
dpb on 17 Dec 2020
But,
{Location1, Location2}=[LV1,RV1]
{Location1, Location2}=[RV1,LV1]
are not the same.
It would then appear that if you want them treated the same you should just replace either RV1 or LV1 with the other in either Location1 or Location2. You could do this on creation of the categorical variable with the optional catnames input variable.

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Accepted Answer

Eric Sofen
Eric Sofen on 17 Dec 2020
You don't say what's not working, but I think you're probably running into findgroups on an array throwing an error. To find groups across variables, input a table. The rest of your code should work fine on the result.
j = findgroups(Data(:,["Subnum","Tp","Location1","Location2","Cond","Freq"])
  3 Comments
Edward Lannon
Edward Lannon on 18 Dec 2020
Thanks for the help.
This is the monster I created to fix the issue. I think I get the resuls I need though. In the process of double checking
T=Data;
Unique=[]
for i=1:height(unique(categories(T.Subnum)));
Z=T;
catsSubnum=unique(categories(Z.Subnum));
indxSubnum = Z.Subnum==catsSubnum(i);
Zi=Z(indxSubnum,:);
for j=1:height(unique(categories(Zi.Tp)));
catsTp=unique(categories(Zi.Tp));
indxTp = Zi.Tp==catsTp(j);
Zp=Zi(indxTp,:);
for m=1:height(unique(categories(Zp.Cond)));
catsCond=unique(categories(Zp.Cond));
indxCond = Zp.Cond==catsCond(m);
Zm=Zp(indxCond,:);
for b=2:height(unique(categories(Zm.Freq)));
catsFreq=unique(categories(Zm.Freq));
indxFreq = Zm.Freq==catsFreq(b);
Zfinal=Zm(indxFreq,:);
A = [Zfinal.Location1 Zfinal.Location2];
[idx,idx]=unique(sort(A')','rows','stable');
Uniquetemp=Zfinal(idx,:);
Unique = [Unique ; Uniquetemp];
end
end
end
end

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