From: Ethan M. <merritt@u.washington.edu> - 2006-09-25 20:31:48
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On Monday 25 September 2006 01:08 pm, Hans-Bernhard Br=F6ker wrote: > CM wrote: > > I suppose this means that the next question from gnuplot's side of > > things is "Should we fiddle with auto configuration to work around > > this?" > > No. The next question from our side is: when will Apple fix this bug > in their implementation of gamma()? Only if the answer to that is > something equivalent to "never" it makes sense to discuss > workarounds. Yes, but... The state of gamma function implementations has changed a bit since gnuplot was first designed. Here is an excerpt from the current documentation: HISTORY 4.2BSD had a gamma() that computed ln(|Gamma(|x|)|), leaving the sign of Gamma(|x|) in the external integer signgam. In 4.3BSD the name was changed to lgamma(), and the man page promises "At some time in the future the name gamma will be rehabilitated and used for the Gamma function" This did indeed happen in 4.4BSD, where gamma() computes the Gamma function (with no effect on signgam). However, this came too late, and we now have tgamma(), the "true gamma" function. The point being that since about 1999 many systems have had a third option, tgamma(), in addition to the gamma() and lgamma() functions that gnuplot's autoconfigure checks for. The syntax and usage of tgamma(), if present, may be more reliable than those of gamma(). =2D-=20 Ethan A Merritt Biomolecular Structure Center University of Washington, Seattle WA |