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Topic: Counting problem
Replies: 4   Last Post: Feb 7, 2013 3:46 PM

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 dpb Posts: 9,850 Registered: 6/7/07
Re: Counting problem
Posted: Feb 6, 2013 5:07 PM

On 2/6/2013 3:40 PM, Erasmus wrote:
> hello everyone, I want count how many times of number meet the specific
> criteria.
> for example, I have two matrix, A and B, I want to count the how many
> times of element meet two criteria,1) the element in A is less than 1;
> 2) the corresponding element(in the same location) in B is larger than 50,.
>
> for example
>
> A= [ 0.1 0.2 0.5
> 0.9 1.3 1.2 0.7 1.2 1.5]
> B=[2 34 43
> 54 55 56
> 62 43 45]
>
> so meet the times meeting these two criteria is 2 times, location[3,1]
> and [2,1]
>

>> ix=find(A<1);
>> iab=intersect(ix,find(B(ix)>50));
>> N=length(iab) % count

N =
2
>> [i,j]=ind2sub(size(A),iab);
>> disp([i j]) % locations

2 1
3 1
>>

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Date Subject Author
2/6/13 dpb
2/7/13 Jos
2/7/13 Steven Lord
2/7/13 Jos