# Filter value from multiple columns

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Commented: Mathieu NOE on 9 Feb 2023
I have the following array named "tNino1_2"
I want to filter the value equal to 1 from columns 20, 21, 22, 23 and 24
The script I'm using is below:
xcol=20:1:24
idx=tNino1_2(tNino1_2(:,xcol)==1,:)
The logical indices in position 1 contain a true value outside of the array bounds.

Mathieu NOE on 9 Feb 2023
hello
I assumed you want all the rows where there is at least one 1 in the columns 20 to 24
xcol=20:1:24;
[r,c] = find(tNino1_2(:,xcol)==1);
[ru,ia,ic] = unique(r);
out = tNino1_2(ru,:);
##### 2 CommentsShow 1 older commentHide 1 older comment
Mathieu NOE on 9 Feb 2023
hello Augusto
as always, my pleasure !

Voss on 9 Feb 2023
Edited: Voss on 9 Feb 2023
"find the values equal to 1 in columns 20 to 24"
[r,c] = find(tNino1_2(:,20:24) == 1)
r = 28×1
96 97 98 107 164 174 107 164 174 175
c = 28×1
1 1 1 1 1 1 2 2 2 2
r is rows and c is columns. Of course, c is relative to columns 20-24 only, so c = 1 means column 20 of the original matrix, c = 2 means column 21, etc.
You can add 19 to c to get the locations of the 1s in the original matrix
c = c+19
c = 28×1
20 20 20 20 20 20 21 21 21 21
Confirm that the elements at those locations are all 1s:
temp = tNino1_2(sub2ind(size(tNino1_2),r,c))
temp = 28×1
1 1 1 1 1 1 1 1 1 1
all(temp == 1)
ans = logical
1
thank you, this script is perfect to identify the rows and columns of the condition I entered

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