Info
Cette question est clôturée. Rouvrir pour modifier ou répondre.
Identifying and modifying the maximum in a matrix.
2 vues (au cours des 30 derniers jours)
Afficher commentaires plus anciens
I have a 100 by 200 matrix of random numbers. I want to identify the max number in each row and set it to 1, while setting everything else equal to 0.
Im able to identify the max, but currently unable to set up the for loop to modify the matrix.
Is anyone able to help?
0 commentaires
Réponses (2)
KSSV
le 6 Juin 2018
A = rand(100,200) ;
iwant = zeros(size(A)) ;
[m,n] = size(A) ;
for i = 1:m
[val,idx] = max(A(i,:)) ;
iwant(i,idx) = 1 ;
end
0 commentaires
Stephen23
le 6 Juin 2018
Modifié(e) : Stephen23
le 6 Juin 2018
This is MATLAB, so no loops are required for this task. It is easy in just one line:
>> M = randi(9,10,20) % fake data
M =
3 6 7 2 2 2 6 2 2 5 6 6 6 7 2 4 7 4 4 4
9 1 5 7 8 5 7 4 5 9 8 6 6 1 6 5 7 2 5 4
4 1 1 7 3 7 6 6 4 7 2 3 3 3 9 8 1 5 1 8
5 2 1 6 9 9 3 6 4 7 3 6 7 2 8 3 4 9 3 3
7 2 2 8 1 6 9 4 9 1 5 4 2 2 8 7 8 2 7 9
2 8 5 9 6 5 7 5 1 8 5 2 1 2 2 1 3 5 9 9
2 2 9 6 9 6 5 6 3 3 2 8 6 8 1 1 1 1 9 9
6 6 2 8 4 8 8 7 6 9 1 4 4 9 4 3 6 9 7 2
2 9 2 2 4 7 8 9 2 9 6 7 1 7 5 3 7 4 5 8
6 4 8 6 9 7 2 9 7 3 7 3 3 1 7 9 3 8 1 6
>> M(:) = bsxfun(@eq,M,max(M,[],2))
M =
0 0 1 0 0 0 0 0 0 0 0 0 0 1 0 0 1 0 0 0
1 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0
0 0 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 1 0 0
0 0 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 0 0 1
0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1
0 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1
0 0 0 0 0 0 0 0 0 1 0 0 0 1 0 0 0 1 0 0
0 1 0 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 0 0
0 0 0 0 1 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0
This marks every instance of the maximum values in the row, If you only want to mark the first instance of the maximum value in the row, then this is also easy:
>> M(:) = M & cumsum(M,2)==1
M =
0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0
0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0
0 commentaires
Cette question est clôturée.
Voir également
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!