# Extract data from matrices and arrays using vectors of coordinates

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I have a matrix and I want to use two vectors of row and column index coordinates in order to extract the elements from it. In particular, I can define a 3 x 3 matrix as
A = [1 2 3; 3 4 5; 8 9 10]
And I want to use two vectors to extract the elements (2,2), (3,1), (1,3). My intention is to do this using the vectors for each corrdinates. I have been trying to do it by writing
A([2 3 1], [2 1 3])
but of course this is not working. I believe that this is a basic sintax issue.
Thank you so much

the cyclist on 28 Sep 2021
Edited: the cyclist on 28 Sep 2021
Use the sub2ind function to convert the subscripts to a linear index into the matrix.
A = [1 2 3; 3 4 5; 8 9 10]
A = 3×3
1 2 3 3 4 5 8 9 10
linearIndex = sub2ind(size(A),[2 3 1], [2 1 3])
linearIndex = 1×3
5 3 7
A(linearIndex)
ans = 1×3
4 8 3
Ariel Kessel Akerman on 28 Sep 2021
Thank you!

R2021a

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