Picking values from n-d array along 3rd dimension
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Hi,
Suppose I have A, an m x n x q array with large integer values.
I have B, an m x n array of integer values in the range of 1:q.
I'd like to pick values from A along the 3rd dimension, so that I obtain C, an m x n array in which for every subscript pair (i,j), m>i>1, n>j>1 the following is true:
x = B(i,j)
C(i,j) = A(i,j,x)
Is there an efficient, loop-free way of doing this?
Many thanks,
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採用された回答
Andrei Bobrov
2013 年 6 月 11 日
編集済み: Andrei Bobrov
2013 年 6 月 11 日
[ii,jj] = ndgrid(1:m,1:n);
ijk = sub2ind(size(A),ii,jj,B);
C = A(ijk);
その他の回答 (2 件)
David Sanchez
2013 年 6 月 11 日
You can assign the value of C without referencing (i,j):
x = B(i,j);
C = A(:,:,x);
And you will have for all i, j that C(i,j) = A(i,j,x)
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