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Re: Selecting Lists Without Null Results


Hello

Try using =!= or UnsameQ

Length[Select[runsTable, (#[[14]] =!= Null) &]]

Length[Select[runsTable, UnsameQ[#[[14]], Null] &]]


Best Regards
Norbert Marxer
www.mec.li


Gregory Lypny wrote:
> I must be doing something wrong as usual.  How come I can select
> list with elements that have the word Null in them as a result of a
> computation, but I cannot exclude them?
>
> I have an array called runsTable with 179 rows, and there are five
> rows with Null in column 14.
>
> So,
>
> 	Length[Select[runsTable, #[[14]] == Null &]
>
> returns 5.
>
> But
>
> 	Length[Select[runsTable, (#[[14]]¬ Null) &]]
>
> returns 0 when it should return 174, that is, 179 minus 5.
>
> 	Am I using the NOT operator incorrectly?
> 
> 	Regards,
> 
> 		Gregory


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