create vectors associated with each entry of an array and save them in a new matrix

Say i have a matrix like A=[1 2; 3 4], and that i need to create 4, vectors each one associated to one entrance of the matrix, such that the first one goes from -1..1, and second from -2..2, and so forth. Wath i try was

for j=1:2 
for k=1:2 
W=linspace(-A(j,k),A(j,k),4) 
end 
end

the problem with that line is that it not save the data. Also i need that to create a new matrix, such that every row be one of the vectors that i mentioned.

Answer 1

[David Young]

Try

W(2*(j-1)+k, :) = linspace(-A(j,k),A(j,k),4)

[Alejandra]

Perfect!! Thanks!

Answer 2

[Matt Tearle]

The easy, brute-force way is just to append the new return from linspace to W each time. Start with W as an empty array:

A=[1 2; 3 4];
W = [];
for j=1:2
    for k=1:2
        W = [W;linspace(-A(j,k),A(j,k),4)];
    end
end

If you're doing this with A large, growing an array like this is not very nice, so instead

A=[1 2; 3 4];

n = size(A,1);
W = zeros(n^2);

for j=1:n
    for k=1:n
        W((j-1)*n+k,:) = linspace(-A(j,k),A(j,k),n^2);
    end
end

[Alejandra]

it also was very helpful, thanks :)