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Date:      Sun, 15 Jul 2001 09:10:08 -0700 (PDT)
From:      Stephen Montgomery-Smith <stephen@math.missouri.edu>
To:        freebsd-bugs@FreeBSD.org
Subject:   Re: bin/28972: gamma returns same result as lgamma
Message-ID:  <200107151610.f6FGA8H87894@freefall.freebsd.org>

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The following reply was made to PR bin/28972; it has been noted by GNATS.

From: Stephen Montgomery-Smith <stephen@math.missouri.edu>
To: freebsd-gnats-submit@FreeBSD.org, stephen@math.missouri.edu,
	Bruce Evans <bde@zeta.org.au>
Cc:  
Subject: Re: bin/28972: gamma returns same result as lgamma
Date: Sun, 15 Jul 2001 11:06:37 -0500

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 How about this change to lgamma.3 ?
 
 
 
 -- 
 Stephen Montgomery-Smith
 stephen@math.missouri.edu
 http://www.math.missouri.edu/~stephen
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 --- lgamma.3-orig	Sun Jul 15 10:59:56 2001
 +++ lgamma.3	Sun Jul 15 11:03:22 2001
 @@ -68,7 +68,7 @@
  returns the sign of \(*G(x).
  .Pp
  .Fn Gamma x
 -returns \(*G(x), with no effect on
 +returns ln\||\(*G(x)|, with no effect on
  .Fa signgam .
  .Sh IDIOSYNCRASIES
  Do not use the expression
 @@ -82,14 +82,14 @@
  Only after
  .Fn lgamma
  has returned can signgam be correct.
 -.Pp
 -For arguments in its range,
 -.Fn gamma
 -is preferred, as for positive arguments
 -it is accurate to within one unit in the last place.
 -Exponentiation of
 -.Fn lgamma
 -will lose up to 10 significant bits.
 +.\.Pp
 +.\For arguments in its range,
 +.\.Fn gamma
 +.\is preferred, as for positive arguments
 +.\it is accurate to within one unit in the last place.
 +.\Exponentiation of
 +.\.Fn lgamma
 +.\will lose up to 10 significant bits.
  .Sh RETURN VALUES
  .Fn Gamma
  and
 @@ -123,4 +123,12 @@
  .Fn gamma
  was originally dedicated to the
  .Fn lgamma
 -function, so some old code may no longer be compatible.
 +function, but then some old code was no longer compatible.
 +Then the name
 +.Fn gamma
 +came to mean a function that computed \(*G(x).  But this caused other
 +compatibility
 +problems, so now 
 +.Fn gamma
 +computes ln\||\(*G(x)|.  But it uses a different algorithm, and it doesn't set 
 +.Fa signgam .
 
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