Check for the length of the matrix

Hello! I'm trying to read a file that will give me a matrix, the dimension is 1000x200, but the problem is that it gives me 998, can I add this length, for example, with zeros?

atmatrix=1x200 uint16; atmatrix all meaning 1000
i=200; 
matrix=fread(fileID,[datmatrix(i),1],'uint8');
if length(matrix)<1000;
    xmatrix=length(1000);
end

Answer 1

[KSSV]

A = rand(3) ; 
B = zeros(5) ; 
[nx,ny] =size(A);
B(1:nx,1:ny) = A ; 

Also read about padarrays

[Lev Mihailov]

I did not quite understand what you meant

atmatrix=1x200 uint16; atmatrix all meaning 1000
i=200; 
matrix=fread(fileID,[datmatrix(i),1],'uint8');
A=zeros(2);
if length(matrix)<1000;
    xmatrix=[matrix A];
end

and this does not work