# Select values from 20 x 15 matrix based on a row vector 1 x 15

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Parthu P on 7 Nov 2019
Commented: Steven Lord on 7 Nov 2019
I'm trying to extract values from matrix A (20 x 15) which are less than values in matrix B (1 x 15). Matrix B has 15 columns with threshold values determined from newspaper analysis. How to extract values from each column of matrix A which are less than values from corresponding columns from matrix B?
I have tried C = A < B; but I'm not able to fix matrix dimension error.
Steven Lord on 7 Nov 2019
Which release of MATLAB are you using? It may be relevant particularly if you're using a release prior to release R2016b, when we introduced implicit expansion.

JESUS DAVID ARIZA ROYETH on 7 Nov 2019
solution:
A(A>=B)=nan;
disp(A)
c=num2cell(A,1);
for k=1:size(c,2)
c{k}(isnan(c{k}))=[];
disp(['Column ' num2str(k)])
disp(c{k})
end
##### 2 CommentsShowHide 1 older comment
JESUS DAVID ARIZA ROYETH on 7 Nov 2019
This works well for the dimensions you indicated, could you save your workspace and attach it? look at an example:
A=rand(20,15);
B=rand(1,15);
A(A>B)=nan;
disp(A)
c=num2cell(A,1);
for k=1:size(c,2)
c{k}(isnan(c{k}))=[];
disp(['Column ' num2str(k)])
disp(c{k})
end

kondepati sudhir kumar on 7 Nov 2019
if use the C = A <B; you wil get the logic matrix. If you have dimensional error then it is better give the c = zeros (size (a));
i hope it works.