# Concatenate a matrix by rows problem

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Ubaldo on 2 Nov 2016
Edited: KSSV on 2 Nov 2016
Hello. I have noticed a strange behavior when concatenating matrix rows. For example, I have those two matrices:
H =
2.0417 0.0208 0.0000
0.0208 2.0200 0.0000
0.0000 0.0000 2.0000
F =
0.1233 0.0801 0.0001
0.4082 0.2002 0.0002
If I type HH = H(:)' I got
HH =
2.0417 0.0208 0.0000 0.0208 2.0200 0.0000 0.0000 0.0000 2.0000
which is correct, as I want to concatenate the matrix row in a long row. On the other hand, if I try FF = F(:)' I got
FF =
0.1233 0.4082 0.0801 0.2002 0.0001 0.0002
which is not correct as the columns are concatenated in a long row.
Is there a way to get always the same result (in my case row concatenation in a long row)?

KSSV on 2 Nov 2016
Edited: KSSV on 2 Nov 2016
If A is any matrix, when you type A(:), it always concatenates column wise irrespective of it's dimensions. If you want to change it's behavior like you mentioned in my case row concatenation in a long row; you have to transpose the matrix and then use :.
F = [0.1233 0.0801 0.0001
0.4082 0.2002 0.0002] ;
F = F' ;
FF = F(:) ;
You put a if condition and proceed with transpose.
if size(F,1) < size(F,2)
F = F' ;
FF = F(:) ;
end

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