# how to store vectors into matrix

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amina amzgh on 19 Aug 2020
Answered: Image Analyst on 20 Aug 2020
I have a vector which takes different values ​​at each iteration I would like to store the result of the vectors in a matrix example iteration 1 A = [1 2 3 4] iteration 2 A = [5 6 7 8] so I will want a result matrix: result = [1 2 3 4; 5 6 7 8]

KSSV on 19 Aug 2020
m = 10 ; n = 4 ;
A = zeros(m,n) ;
for i = 1:m
A(i,:) = rand(1,n) ;
end

David Hill on 19 Aug 2020
for k=1:100
end

Image Analyst on 19 Aug 2020
Try this:
result = zeros(numIterations, 4);
for k = 1 : numIterations
% Get A somehow, then
result(k, :) = A;
end

Ruger28 on 19 Aug 2020
Edited: Ruger28 on 19 Aug 2020
A = [1 2 3 4];
B = [5 6 7 8];
C = [A;B]
In a loop:
Sum_Matrix = []; % pre-allocate if you know how many total elements in array you'll have
A = [1 2 3 4];
for ii = 1:100 % number of iterations
% whatever math to get you your vector
B = A * ii; % example
Sum_Matrix = [Sum_Matrix;B];
end
##### 2 CommentsShowHide 1 older comment
Ruger28 on 19 Aug 2020
You're welcome.

Image Analyst on 20 Aug 2020
If the "A" is really as predictable as you implied in your comment to Ruger28 (and not general as I assumed in my Answer), and you want a vectorized way to do it, you can use reshape:
numIterations = 5; % Whatever you want/need.
result = reshape([1 : numIterations*4]', 4, [])'
You get:
result =
1 2 3 4
5 6 7 8
9 10 11 12
13 14 15 16
17 18 19 20
Of course, this vectorized version is the more MATLAB-y way to do it. No for loops are needed at all. (This way also uses your preferred and better variable name of "result".)