Typo: f=:_.&=
----- Original Message -----
From: R&S HUI <[EMAIL PROTECTED]>
Date: Thursday, July 6, 2006 5:57 pm
Subject: Re: [Jprogramming] _. and/or
> f=: -.&= will test for _. , but you should be careful
> about calling it ISNULL. I believe there are other
> nulls and if your data came from an external source
> f may not test correctly for those.
>
> If you want to be totally foolproof, research into
> what 64-bit floats can be NaNs, and write a function
> to look for those patterns in the 3!:1 or 3!:3
> representations. The details are left as an exercise
> for the reader.
>
>
>
> ----- Original Message -----
> From: bill lam <[EMAIL PROTECTED]>
> Date: Thursday, July 6, 2006 5:18 pm
> Subject: Re: [Jprogramming] _. and/or
>
> > R&S HUI wrote:
> > > When an argument of a verb is _. , all bets are off.
> > > ("All bets are off" is an idiom meaning: anything can
> > > happen and don't blame me if it does.)
> >
> > What is the verb that test for _. which is guaranteed to work?
> >
> > isnull _. -> 1
> > isnull 1 -> 0
>
>
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