Create a permutation of elements in the same position
1 vue (au cours des 30 derniers jours)
Afficher commentaires plus anciens
Salwa Mostafa
le 15 Fév 2022
Commenté : Salwa Mostafa
le 15 Fév 2022
I have coordinates of points x = [x_1 x_2], y =[ y_1 y_2 ] z = [z_1 z_2 ]
I want to create a matrix with all permutation but the coordinates are in the same position
[ x_1 y_1 z_2;
x_1 y_2 z_2;
x_1 y_1 z_1;
x_1 y_2 z_2;
x_2 y_1 z_2;
x_2 y_2 z_2;
x_2 y_1 z_1;
x_2 y_2 z_2; ]
but the coordinates is changing so it can be x,y,z,v,w I want to write it for a general number of coordinates.
0 commentaires
Réponse acceptée
William Rose
le 15 Fév 2022
I see that you have already done it for 2 pairs of coordinates. Here is a way to do it for N coordinates.
N=3;
x=rand(1,N); y=rand(1,N); z=rand(1,N);
A=zeros(N^3,3); %initialize array
for i=1:N
for j=1:N
for k=1:N
A(N^2*(i-1)+N*(j-1)+k,:)=[x(i),y(j),z(k)];
end
end
end
Try it. Good luck.
0 commentaires
Plus de réponses (2)
DGM
le 15 Fév 2022
Modifié(e) : DGM
le 15 Fév 2022
Consider the example:
% input coordinates
x = [1 2];
y = [11 22];
z = [111 222];
% create the index array
m = (dec2bin(0:7,3) == '1') + 1;
% all combinations in order
xyz = [x(m(:,1)); y(m(:,2)); z(m(:,3))].'
Or more generally:
x = [1 2 3];
y = [11 22 33];
z = [111 222 333];
% create the index array
nx = numel(x);
m = repmat((1:nx)',[nx*2 1]);
m = [repelem(m(1:size(m,1)/nx,1),nx) m];
m = [repelem(m(1:size(m,1)/nx,1),nx) m];
% get the combinations like before
xyz = [x(m(:,1)); y(m(:,2)); z(m(:,3))].'
3 commentaires
Voir également
Catégories
En savoir plus sur Resizing and Reshaping Matrices dans Help Center et File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!