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32 .\" from: @(#)lgamma.3 6.6 (Berkeley) 12/3/92
33 .\" $FreeBSD: src/lib/msun/man/lgamma.3,v 1.7.2.6 2003/01/04 01:01:29 jdp Exp $
34 .\" $DragonFly: src/lib/msun/man/Attic/lgamma.3,v 1.2 2003/06/17 04:26:52 dillon Exp $
44 .Nd log gamma functions, gamma functions
65 return ln\||\(*G(x)| where
66 .Bd -unfilled -offset indent
67 \(*G(x) = \(is\d\s8\z0\s10\u\u\s8\(if\s10\d t\u\s8x\-1\s10\d e\u\s8\-t\s10\d dt for x > 0 and
69 \(*G(x) = \(*p/(\(*G(1\-x)\|sin(\(*px)) for x < 1.
77 returns the sign of \(*G(x).
82 are deprecated aliases for
88 Do not use the expression
89 .Dq Li signgam\(**exp(lgamma(x))
90 to compute g := \(*G(x).
91 Instead use a program like this (in C):
92 .Bd -literal -offset indent
93 lg = lgamma(x); g = signgam\(**exp(lg);
100 has returned can signgam be correct.
102 .\"For arguments in its range,
104 .\"is preferred, as for positive arguments
105 .\"it is accurate to within one unit in the last place.
108 .\"will lose up to 10 significant bits.
115 return appropriate values unless an argument is out of range.
116 Overflow will occur for sufficiently large positive values, and
117 non-positive integers.
120 the reserved operator is returned,
125 \."For large non-integer negative values,
139 as a function which computed \(*G(x).
140 This version was used in
144 was originally dedicated to the
147 and that usage was restored by switching to Sun's fdlibm in
151 standard specifies a function
153 for computing \(*G(x).
154 This function is currently unimplemented in this library.