Curious
2*_.
0
2+_.
_.
>:_.
_.
+:_.
0
x:_.
_
i=.1%0
i
_
ix=.1%0x
ix
_
i=ix
1
i-i
_.
ix-ix
|domain error
| ix -ix
ix-i
_.
R&S HUI wrote:
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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