Re: using find function to wrap set functions

[Francesco Potortì]

>> I would like to use "find" with some set functions, because a for loop takes
>> too much time. For example, I have a large array  aa (100000,10) where each
>> row has 10 numbers. I want to use the complement function to find all rows
>> that contain the values [12 54 77]. This code is too slow:
>> 
>> for ix = 1:rows(aa)
>>      if (columns(complement (aa(ix,:), [12 54 77])) == 0)
>>      ...save ix...
>>      endif
>> endfor  
>> 
>> I would like to wrap this in a find function, but I don't know the syntax
>> for this.
>> 
>> find(columns(complement (aa(:,:), [8 43])) == 0); does not work.
>> 
>
>This solution is probably completely stupid, but what about 
>
>find(sum(aa==12 | aa==54 | aa==77, 2) == 3)

This only works if there are not duplicates in each row.  But this one
(untested) should work:

find(all(any(aa'==12), any(aa'==54), any(aa'==77)))

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