MATLAB: Permuting one matrix w.r.t. another matrix

MATLABmatrixmatrix manipulationsub2ind

I have two large matrices a and b. for instance
a=[1 2 3;4 5 6; 7 8 9; 10 11 12];
b=[1 3 2; 2 1 3; 3 2 1; 3 1 2];
how to get the matrix a in the form:
a = [1 3 2; 5 4 6; 9 8 7; 12 10 11]
This is actually the permutation of matrix a w.r.t. matrix b.
How to achieve this goal in matlab?

Best Answer

Use sub2ind, e.g.:
>> a = [1,2,3;4,5,6;7,8,9;10,11,12]
a =
    1    2    3
    4    5    6
    7    8    9
   10   11   12
>> b = [1,3,2;2,1,3;3,2,1;3,1,2]
b =
    1    3    2
    2    1    3
    3    2    1
    3    1    2
>> S = size(a);
>> [R,~] = ndgrid(1:S(1),1:S(2));
>> a = a(sub2ind(S,R,b))
a =
    1    3    2
    5    4    6
    9    8    7
   12   10   11
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