gmane.lisp.scheme.gauche

asinh limit

I'm not sure this is a bug, but it tripped me in a filter computation:

  (asinh 1000000.0)

returns 

  -inf.0-inf.0i

gosh> (sinh 14.5086577385245)
1000000.0000000303
gosh> (asinh (sinh 14.5086577385245))
-inf.0-inf.0i
gosh> (gauche-version)
"0.8.12"

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Shiro Kawai | 24 Dec 14:20

Re: asinh limit

Oops.
It's a bug in the code that tries to avoid numerical unstability.
It should've cut only the range of -Re(z) being very large.
Thanks for reporting this.

--shiro

From: "Bill Schottstaedt" <bil <at> ccrma.Stanford.EDU>
Subject: [Gauche-devel] asinh limit
Date: Mon, 24 Dec 2007 04:53:32 -0800

> I'm not sure this is a bug, but it tripped me in a filter computation:
> 
>   (asinh 1000000.0)
> 
> returns 
> 
>   -inf.0-inf.0i
> 
> gosh> (sinh 14.5086577385245)
> 1000000.0000000303
> gosh> (asinh (sinh 14.5086577385245))
> -inf.0-inf.0i
> gosh> (gauche-version)
> "0.8.12"
> 
> 
> 
> -------------------------------------------------------------------------
> This SF.net email is sponsored by: Microsoft

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