Exchange position of elements in an array
3 views (last 30 days)
Show older comments
Hi given two arrays
SP = [1 2 3 4 8 11 13 14 15 16 18 19 20];
Y= [24 18 18 18 18 18 18 18 18 18 18 18 18];
I create an array
S= [19 1 4 14 20 11 20 13 18 11 8 16 14 13 3 13 8 1 15 13 16 14 1 11 3 4 20 19 8 20 14 18 3 11 13 13 11 20 11 20 16 2 20 15 1 11 4 13 18 20 3 15 11 8 16 8 14 14 1 8 14 8 1 16 3 20 8 18 16 4 15 2 8 2 3 16 14 3 15 2 1 18 13 4 18 4 20 18 14 4 2 2 2 4 8 11 20 13 3 11 16 19 2 18 3 11 19 1 13 3 19 11 15 3 14 19 16 2 8 13 3 11 20 19 18 18 19 15 14 16 8 1 3 18 18 4 14 15 15 18 1 3 4 1 15 2 11 1 16 15 8 13 16 16 1 19 16 13 19 8 19 11 20 1 15 2 13 14 20 1 2 8 14 4 15 15 4 1 1 3 18 1 4 4 1 8 11 2 1 18 14 18 13 8 14 19 3 18 11 4 11 20 16 1 15 15 19 2 19 3 2 20 13 19 4 13 15 4 16 1 8 19 1 3 19 16 2 4 14 2 14 1 16 19 15 20 2 20 13 18];
Where 1 is repeated 24 times, 2 is repeated 18 times, 3 is repeated 18 times and so on. So the array SP tells us the diversity of elements and Y how many times they are repeated in S.
Now what I want to do is to exchange randomly the position of the elements inside S.
In particular I want to follow two rules:
1) Just some elements can exchange with eachother. In particular considering the matrix BB
BB= [1 2 3 4 0 11 14 15;
0 0 0 8 13 16 0 0;
0 0 0 0 0 18 0 0;
0 0 0 0 0 19 0 0;
0 0 0 0 0 20 0 0];
We can exchange each other just the element on the same column. It means that a 11 can just exchange with 16,18,19,20. While 4 can just exchange with 8. Obviously if there is just one number on the columns it will remain in its position.
2) I want that the elements exchange their position randomly with the one on the same columns of BB. But I don't want to substitute a value with another random value on the same colums! This means that at the end, the number of repetitons indicated in Y will be respected in the new array
May someone can help me with this code?
0 Comments
Accepted Answer
David Hill
on 7 Oct 2019
for i=1:size(BB,2)
x=S(ismember(S,BB(:,i)));
S(ismember(S,BB(:,i)))=x(randperm(length(x)));
end
0 Comments
More Answers (0)
See Also
Categories
Find more on Logical in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!