# How do you initialize an N*M matrix?

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Harry on 26 Jun 2013
Commented: israt fatema on 25 Aug 2021
From the MATLAB help, it says to use:
M = matrix(N, M)
but when I apply this it says that the function 'matrix' is not recognized.
Undefined function 'matrix' for input arguments of type 'double'.
Error in experimental (line 1)
M = matrix(3,3)
Tulike on 12 Jul 2017
M=zeros(N,M)

Leah on 26 Jun 2013
Edited: MathWorks Support Team on 27 Nov 2018
To initialize an N-by-M matrix, use the “zeros” function. For example, create a 3-by-5 matrix of zeros:
A = zeros(3,5);
You can then later assign specific values to the elements of “A”.
israt fatema on 25 Aug 2021
Can you please show me how to assign value to A after initialize the N x M matrix? For example i need to create a vector 5 x 5 and with values x = 20 35 49 64 23

Lokesh Ravindranathan on 26 Jun 2013
Edited: Lokesh Ravindranathan on 26 Jun 2013
I am assuming you are trying to create an empty matrix of zeros of dimensions N*M. You can try the following instead
M = zeros(3,3)
This creates a matrix of zeros of size 3*3.
##### 2 CommentsShowHide 1 older comment
Lokesh Ravindranathan on 26 Jun 2013
Oh. Thanks Isakson. I will update my answer. My MATLAB did not have symbolic Math toolbox.

Nitin on 26 Jun 2013
you could initialize the matrix,
M = zeros(n,m);

Pau on 17 Oct 2018
This should make the trick
M = double.empty(N,M,0);
https://uk.mathworks.com/help/matlab/ref/empty.html