How to create three columns for matrix after indexing

Question

Mahesh 2015-2-18

0
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https://ww2.mathworks.cn/matlabcentral/answers/179144-how-to-create-three-columns-for-matrix-after-indexing

编辑： Jos 2015-2-18

Dear all, I have a 8X8X8 three dimensional matrix. I would like to create 512X4 matrix so that first column give the position of x, second column the position of y and third one for z position.

I have a code like this

nx = size(dyzw,1);
ny = size(dyzw,2);
nz = size(dyzw,1);
N = nx*ny*nz;
bigData = dyzw(:);
bigMatrix = zeros(N, 4);
for i = 1: N
    bigMatrix(i,4) = bigData(i);
    for j = 1: nx
        for k = 1: ny
            for l = 1:nz
                bigMatrix(i,1) =j;
                bigMatrix(i,2) =k;
                bigMatrix(i,3) =l;
            end 
        end
    end
end

But I failed to produce the matrix as I want. Could you please check my code please.

Thanks

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Answer 1

Jos 2015-2-18

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https://ww2.mathworks.cn/matlabcentral/answers/179144-how-to-create-three-columns-for-matrix-after-indexing#answer_168488

编辑：Jos 2015-2-18

在 MATLAB Online 中打开

Hi Mahesh,

this will do what you want

nx = size(dyzw,1);
ny = size(dyzw,2);
nz = size(dyzw,3);
N = nx*ny*nz;
bigMatrix = zeros(N,4);
i = 0;
for j = 1:nx
    for k = 1:ny
        for l = 1:nz
            i = i+1;
            bigMatrix(i,1) = j;
            bigMatrix(i,2) = k;
            bigMatrix(i,3) = l;
            bigMatrix(i,4) = dyzw(j,k,l);
        end 
    end
end