Replacing elements in a vector

5 visualizzazioni (ultimi 30 giorni)
L'O.G.
L'O.G. il 16 Lug 2022
Commentato: L'O.G. il 17 Lug 2022
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];

Risposta accettata

Paul
Paul il 17 Lug 2022
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 Commenti
Paul
Paul il 17 Lug 2022
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. il 17 Lug 2022
Thank you. That is really neat!

Accedi per commentare.

Più risposte (1)

DGM
DGM il 16 Lug 2022
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 Commento
L'O.G.
L'O.G. il 16 Lug 2022
Thank you, but no, that's not what I want. I've edited my question to hopefully make it clearer.

Accedi per commentare.

Prodotti


Release

R2021b

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by