Replacing elements in a vector

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The values of an array match the index of elements in a vector. For example, the value of 5 in array1 below corresponds to whatever is in index 5 in vector1, i.e. the number 3 in this case. So how do I replace the value of the original number in array1 in the example by the number at the corresponding index in vector1? I realize this is a little confusing, so here's a mini example of what I want to do:
array1 = [1 2; 4 2; 5 5; 4 2];
vector1 = [2 1 1 4 3 4];
result = [2 1; 4 1; 3 3; 4 1];

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Paul
Paul 2022-7-17
array1 = [1 2; 4 2; 5 5; 4 2];
vector1 = [2 1 1 4 3 4];
result = [2 1; 4 1; 3 3; 4 1]
result = 4×2
2 1 4 1 3 3 4 1
result1 = vector1(array1)
result1 = 4×2
2 1 4 1 3 3 4 1
  3 个评论
Paul
Paul 2022-7-17
vector1(array1) treats each entry of array1 as the linear index into vector1. The output takes the same shape as array1. It's the same as
array1 = [1 2; 4 2; 5 5; 4 2];
vector1 = [2 1 1 4 3 4];
reshape(vector1(array1(:)),size(array1))
ans = 4×2
2 1 4 1 3 3 4 1
L'O.G.
L'O.G. 2022-7-17
Thank you. That is really neat!

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更多回答(1 个)

DGM
DGM 2022-7-16
Your example isn't consistent. I'm assuming you want this:
A = [10 20; 30 40; 50 60];
idx = [2 1; 1 4; 3 3];
B = A.';
B = B(idx)
B = 3×2
20 10 10 40 30 30
  1 个评论
L'O.G.
L'O.G. 2022-7-16
Thank you, but no, that's not what I want. I've edited my question to hopefully make it clearer.

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