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From: sam@kalessin.jpl.nasa.gov (Sam Sirlin)
Newsgroups: comp.lang.apl
Subject: Re: Factorials in J
Message-ID: <1991Mar11.202526.20774@jato.jpl.nasa.gov>
Date: 11 Mar 91 20:25:26 GMT
References: <1991Mar9.040541.28914@aplcen.apl.jhu.edu>
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Reply-To: sam@kalessin.jpl.nasa.gov (Sam Sirlin)
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In article <1991Mar9.040541.28914@aplcen.apl.jhu.edu>, simpson@aplcen.apl.jhu.edu (Simpson David Grant) writes:
|> In article <1991Mar9.040541.28914@aplcen.apl.jhu.edu>, simpson@aplcen.apl.jhu.edu (Simpson David Grant) writes:
|> 
|> Can someone explain what is happening when I try to calculate
|> factorials in the following J session?  I do this right after
|> starting up J (version 3):
|> 
|>    !9
|> 362880
|>    !174
|> 1.7=e309
|>    !9
|> 1
|> 
|> All following attempts to calculate factorials also produce 1.
|> What gives?
|> 
|>                                  David Simpson

What version/machine? With 2.9 on my SPARC 1 I get:


   !9
362880
   !174
_
   !9
362880
   !4
24


which looks fine. Version 2.4 on my PCAT bombs when it trys !174 (overflow). 
Sounds like infinity doesn't quite work in your version.

-- 
Sam Sirlin
Jet Propulsion Laboratory         sam@kalessin.jpl.nasa.gov