How to save output from iteration?

i have an array a=[1;2;2;3;4;4;4;4]; when i type

for i=1:3
[~,col]=find(a==1)
end

it only results col=1, i wanna save all of the col, it's like

col=1
    1
    1

what should i do? thank you

[Leah]

it's not clear what you are looping over since "i" does not appear inside the for loop. Also your desired output for col, doesn't really make sense since 1 only appears in the first entry of a. What do the three outputs for col mean?

[Matt Kindig]

@Tara: For what it's worth, you can accomplish the same thing more efficiently by using ismember(), as:

[temp,locs]=ismember(a, 1:3);
%  'locs' will contain positions where 1,2,and 3 are found in 'a'

Answer 1

[Walter Roberson]

for i = 1 : 3
  [~, col{i}] = find(a==1);
end

Notice the switch to cell arrays. This is needed because any given value might occur 0, 1, or many times instead of exactly once.

Also notice you are doing exactly the same "find" each time. Perhaps you wanted to find over a(i,:) ?

[Tara]

@walter,how about my code bellow

for i=1:length(maxprob)
pred=find(numb==3); % this results index of number
if length(pred)>1
pred=0; 
else
pred;
end
end

it only results the final answer, not all the result of iteration. can you help me? thank you