how to store vectors into matrix

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amina amzgh
amina amzgh il 19 Ago 2020
Risposto: Image Analyst il 20 Ago 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]

Risposte (5)

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

David Hill
David Hill il 19 Ago 2020
for k=1:100
A(k,:)=randi(100,1,4);%your vectors
end

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

Ruger28
Ruger28 il 19 Ago 2020
Modificato: Ruger28 il 19 Ago 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 Commenti
amina amzgh
amina amzgh il 19 Ago 2020
it works perfectly , i just donc need to multiply ii by A ....
i really thank u a lot...........
Ruger28
Ruger28 il 19 Ago 2020
You're welcome.

Accedi per commentare.


Image Analyst
Image Analyst il 20 Ago 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".)

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