How to get the first five minimum number for a list

7 vues (au cours des 30 derniers jours)
amj
amj le 11 Fév 2018
Commenté : amj le 11 Fév 2018
Hi,
I would like to get the index number of the first five minimum number from the list. This is my code:
list = [4,10,1,2,7,12,5,6,10,8];
min=list(1,1)
ind = 1;
N = length(list)
t= 0;
while (t<5)
for n = 2:N
if min>list(n)
ind=n;
min=list(n);
end
end
minIndexList(1,t+1) =ind ;
t = t+1;
end
disp(minIndexList)
However, the code just stored and repeat the index of the minimum Fors insance, minIndexList just stored >> 3,3,3,3,3. By right, the minIndexList should store = 3,4,1,7,8. Do anyone can help me to solve this problem? Thank you in advance
  1 commentaire
Walter Roberson
Walter Roberson le 11 Fév 2018
What behaviour do you want if the list has duplicates? Are you looking for the indices of the 5 smallest unique values, or the 5 smallest values including duplicates?
What output would you expect for the list [1 1 1 2 2 2 2 3 3 3 3 3 3] ? You "use up" 3 of the output slots for the 1's, so then you have 2 output slots remaining but 4 locations that have the same minimum value: how do you decide which of those 4 locations you give the index of?

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Birdman
Birdman le 11 Fév 2018
Use the simple code below:
[~,idx]=ismember(sort(list),list);
idx=idx(1:5)
  3 commentaires
Birdman
Birdman le 11 Fév 2018
Yes but still does the job.
amj
amj le 11 Fév 2018
Thanks a million Birdman & Walter Roberson

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Plus de réponses (1)

Walter Roberson
Walter Roberson le 11 Fév 2018
Modifié(e) : Walter Roberson le 11 Fév 2018
  1 commentaire
amj
amj le 11 Fév 2018
Thank you Walter Roberson. Yeah ..indeed true. Any idea if the repeating indexes occur?

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