Resurrect Lite1's gamma() as C99's tgamma(). Minimal changes.
This commit is contained in:
Bruce Evans
parent
052ce5262c
commit
46d7c2979e
@ -62,13 +62,15 @@ ARCH_SRCS = e_acos.S e_asin.S e_atan2.S e_exp.S e_fmod.S e_log.S e_log10.S \
|
||||
# Broken
|
||||
# ARCH_SRCS+= s_log1p.S
|
||||
|
||||
.PATH: ${.CURDIR}/bsdsrc
|
||||
.PATH: ${.CURDIR}/man
|
||||
.PATH: ${.CURDIR}/src
|
||||
|
||||
CFLAGS+= -D_IEEE_LIBM -D_ARCH_INDIRECT=${ARCH_PREFIX}
|
||||
|
||||
LIB= m
|
||||
COMMON_SRCS = e_acos.c e_acosf.c e_acosh.c e_acoshf.c e_asin.c e_asinf.c \
|
||||
COMMON_SRCS= b_exp.c b_log.c b_tgamma.c \
|
||||
e_acos.c e_acosf.c e_acosh.c e_acoshf.c e_asin.c e_asinf.c \
|
||||
e_atan2.c e_atan2f.c e_atanh.c e_atanhf.c e_cosh.c e_coshf.c e_exp.c \
|
||||
e_expf.c e_fmod.c e_fmodf.c e_gamma.c e_gamma_r.c e_gammaf.c \
|
||||
e_gammaf_r.c e_hypot.c e_hypotf.c e_j0.c e_j0f.c e_j1.c e_j1f.c \
|
||||
@ -147,7 +149,7 @@ MLINKS+=ieee_test.3 scalb.3 ieee_test.3 scalbf.3
|
||||
MLINKS+=ieee_test.3 significand.3 ieee_test.3 significandf.3
|
||||
MLINKS+=j0.3 j1.3 j0.3 jn.3 j0.3 y0.3 j0.3 y1.3 j0.3 y1f.3 j0.3 yn.3
|
||||
MLINKS+=j0.3 j0f.3 j0.3 j1f.3 j0.3 jnf.3 j0.3 y0f.3 j0.3 ynf.3
|
||||
MLINKS+=lgamma.3 gamma.3 lgamma.3 lgammaf.3 lgamma.3 gammaf.3
|
||||
MLINKS+=lgamma.3 gamma.3 lgamma.3 gammaf.3 lgamma.3 lgammaf.3 lgamma.3 tgamma.3
|
||||
MLINKS+=rint.3 rintf.3
|
||||
MLINKS+=sin.3 sinf.3
|
||||
MLINKS+=sinh.3 sinhf.3
|
||||
|
||||
@ -117,6 +117,7 @@ ic(lnhuge, 7.1602103751842355450E2, 9, 1.6602B15B7ECF2)
|
||||
ic(lntiny,-7.5137154372698068983E2, 9, -1.77AF8EBEAE354)
|
||||
ic(invln2, 1.4426950408889633870E0, 0, 1.71547652B82FE)
|
||||
|
||||
#if 0
|
||||
double exp(x)
|
||||
double x;
|
||||
{
|
||||
@ -159,6 +160,7 @@ double x;
|
||||
/* exp(INF) is INF, exp(+big#) overflows to INF */
|
||||
return( finite(x) ? scalb(1.0,5000) : x);
|
||||
}
|
||||
#endif
|
||||
|
||||
/* returns exp(r = x + c) for |c| < |x| with no overlap. */
|
||||
|
||||
|
||||
@ -367,6 +367,7 @@ static double logF_tail[N+1] = {
|
||||
-.00000000000017239444525614834
|
||||
};
|
||||
|
||||
#if 0
|
||||
double
|
||||
#ifdef _ANSI_SOURCE
|
||||
log(double x)
|
||||
@ -437,6 +438,7 @@ log(x) double x;
|
||||
u2 += logF_tail[N]*m;
|
||||
return (u1 + u2);
|
||||
}
|
||||
#endif
|
||||
|
||||
/*
|
||||
* Extra precision variant, returning struct {double a, b;};
|
||||
|
||||
@ -34,7 +34,7 @@
|
||||
#ifndef lint
|
||||
static char sccsid[] = "@(#)gamma.c 8.1 (Berkeley) 6/4/93";
|
||||
#endif /* not lint */
|
||||
include <sys/cdefs.h>
|
||||
#include <sys/cdefs.h>
|
||||
__FBSDID("$FreeBSD$");
|
||||
|
||||
/*
|
||||
@ -138,7 +138,7 @@ static int endian;
|
||||
#endif
|
||||
|
||||
double
|
||||
gamma(x)
|
||||
tgamma(x)
|
||||
double x;
|
||||
{
|
||||
struct Double u;
|
||||
@ -225,7 +225,7 @@ small_gam(x)
|
||||
TRUNC(r.a);
|
||||
r.b += (t - r.a);
|
||||
}
|
||||
/* Return r*gamma(y). */
|
||||
/* Return r*tgamma(y). */
|
||||
yy = ratfun_gam(y - x0, 0);
|
||||
y = r.b*(yy.a + yy.b) + r.a*yy.b;
|
||||
y += yy.a*r.a;
|
||||
@ -330,9 +330,9 @@ neg_gam(x)
|
||||
}
|
||||
y = one-x;
|
||||
if (one-y == x)
|
||||
y = gamma(y);
|
||||
y = tgamma(y);
|
||||
else /* 1-x is inexact */
|
||||
y = -x*gamma(-x);
|
||||
y = -x*tgamma(-x);
|
||||
if (sgn < 0) y = -y;
|
||||
return (M_PI / (y*z));
|
||||
}
|
||||
|
||||
@ -39,8 +39,9 @@
|
||||
.Nm lgamma ,
|
||||
.Nm lgammaf ,
|
||||
.Nm gamma ,
|
||||
.Nm gammaf
|
||||
.Nd log gamma functions, gamma functions
|
||||
.Nm gammaf ,
|
||||
.Nm tgamma
|
||||
.Nd log gamma functions, gamma function
|
||||
.Sh LIBRARY
|
||||
.Lb libm
|
||||
.Sh SYNOPSIS
|
||||
@ -56,6 +57,8 @@
|
||||
.Fn gamma "double x"
|
||||
.Ft float
|
||||
.Fn gammaf "float x"
|
||||
.Ft double
|
||||
.Fn tgamma "double x"
|
||||
.Sh DESCRIPTION
|
||||
.Fn lgamma x
|
||||
and
|
||||
@ -83,6 +86,9 @@ are deprecated aliases for
|
||||
and
|
||||
.Fn lgammaf ,
|
||||
respectively.
|
||||
.Fn tgamma x
|
||||
returns \(*G(x), with no effect on
|
||||
.Fa signgam .
|
||||
.Sh IDIOSYNCRASIES
|
||||
Do not use the expression
|
||||
.Dq Li signgam\(**exp(lgamma(x))
|
||||
@ -97,14 +103,14 @@ Only after
|
||||
or
|
||||
.Fn lgammaf
|
||||
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 tgamma
|
||||
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 ,
|
||||
.Fn gammaf ,
|
||||
@ -121,11 +127,18 @@ and
|
||||
.Va errno
|
||||
is set to
|
||||
.Er ERANGE .
|
||||
\."For large non-integer negative values,
|
||||
\.".Fn gamma
|
||||
\."will underflow.
|
||||
For large non-integer negative values,
|
||||
.Fn tgamma
|
||||
will underflow.
|
||||
.Sh SEE ALSO
|
||||
.Xr math 3
|
||||
.Sh STANDARDS
|
||||
The
|
||||
.Fn lgamma
|
||||
and
|
||||
.Fn tgamma
|
||||
functions are expected to conform to
|
||||
.St -isoC-99 .
|
||||
.Sh HISTORY
|
||||
The
|
||||
.Fn lgamma
|
||||
@ -146,8 +159,6 @@ function,
|
||||
and that usage was restored by switching to Sun's fdlibm in
|
||||
.Fx 1.1.5 .
|
||||
The
|
||||
.St -isoC-99
|
||||
standard specifies a function
|
||||
.Fn tgamma
|
||||
for computing \(*G(x).
|
||||
This function is currently unimplemented in this library.
|
||||
function appeared in
|
||||
.Fx 5.0 .
|
||||
|
||||
@ -153,6 +153,7 @@ double logb(double);
|
||||
double nextafter(double, double);
|
||||
double remainder(double, double);
|
||||
double scalb(double, double);
|
||||
double tgamma(double);
|
||||
|
||||
#ifndef __cplusplus
|
||||
int matherr(struct exception *);
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user