# How to add NaN values to a matrix?

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Yelitza Perez on 13 Nov 2020
Commented: Cris LaPierre on 14 Nov 2020
Hi, I need to add NaN values to two matrices. One is a 1x48000 and it needs to be 1x48449 and the other is 4x48000 and it needs to be 4x48449. How can I do that? I need to add these extra values because the 1x48000 matrix is beign concatinated with another matrix of size 1x48449. So I was thinking to add some NaN values or maybe substract the 449 extra values from the second matrix.
Can anyone help me understand this better? Thank you for any help you can provide.

Cris LaPierre on 13 Nov 2020
Use the missing function.
% Define a 4x5 matrix
A=ones(4,5);
% Turn into a 4x9
A(:,end+1:9)=missing
A = 4×9
1 1 1 1 1 NaN NaN NaN NaN 1 1 1 1 1 NaN NaN NaN NaN 1 1 1 1 1 NaN NaN NaN NaN 1 1 1 1 1 NaN NaN NaN NaN
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Cris LaPierre on 14 Nov 2020
That's what my code does. I first defined the matrix A, then I increased its size by adding NaNs.
It would appear you know the size of your matrices, so adapt the code I shared to increase the size of your smaller matrix so that it is the size of the larger one.

Setsuna Yuuki. on 13 Nov 2020
Edited: Setsuna Yuuki. on 13 Nov 2020
A = rand(1,48000) %Matrix of example (1x48000)
B = rand(1,48449) %Matrix of example (4x48449)
C = [A;B(1:48000)] %You can take the matrix values from 1 to 48000, and concatenate.
and
A = rand(4,48000) %Matrix of example (4x48000)
B = rand(4,48449) %Matrix of example (4x48449)
C = [A;B(1:4,1:48000)] %You can take the matrix values from 1 to 48000, and concatenate.
##### 2 CommentsShowHide 1 older comment
Setsuna Yuuki. on 14 Nov 2020
A and B are your matrix, rand is a method to create random data, but is only a example.
C=[A B(1:48000)] %concatenate A matrix and B matrix, but only from element 1 to element 48000 of B matrix
This method removes values from matrix B does not add NaN in matrix A