centos man page for tgammal

Query: tgammal

OS: centos

Section: 3

Format: Original Unix Latex Style Formatted with HTML and a Horizontal Scroll Bar

TGAMMA(3)						     Linux Programmer's Manual							 TGAMMA(3)

NAME
tgamma, tgammaf, tgammal - true gamma function
SYNOPSIS
#include <math.h> double tgamma(double x); float tgammaf(float x); long double tgammal(long double x); Link with -lm. Feature Test Macro Requirements for glibc (see feature_test_macros(7)): tgamma(), tgammaf(), tgammal(): _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L; or cc -std=c99
DESCRIPTION
The Gamma function is defined by Gamma(x) = integral from 0 to infinity of t^(x-1) e^-t dt It is defined for every real number except for nonpositive integers. For nonnegative integral m one has Gamma(m+1) = m! and, more generally, for all x: Gamma(x+1) = x * Gamma(x) Furthermore, the following is valid for all values of x outside the poles: Gamma(x) * Gamma(1 - x) = PI / sin(PI * x)
RETURN VALUE
On success, these functions return Gamma(x). If x is a NaN, a NaN is returned. If x is positive infinity, positive infinity is returned. If x is a negative integer, or is negative infinity, a domain error occurs, and a NaN is returned. If the result overflows, a range error occurs, and the functions return HUGE_VAL, HUGE_VALF, or HUGE_VALL, respectively, with the correct mathematical sign. If the result underflows, a range error occurs, and the functions return 0, with the correct mathematical sign. If x is -0 or +0, a pole error occurs, and the functions return HUGE_VAL, HUGE_VALF, or HUGE_VALL, respectively, with the same sign as the 0.
ERRORS
See math_error(7) for information on how to determine whether an error has occurred when calling these functions. The following errors can occur: Domain error: x is a negative integer, or negative infinity errno is set to EDOM. An invalid floating-point exception (FE_INVALID) is raised (but see BUGS). Pole error: x is +0 or -0 errno is set to ERANGE. A divide-by-zero floating-point exception (FE_DIVBYZERO) is raised. Range error: result overflow errno is set to ERANGE. An overflow floating-point exception (FE_OVERFLOW) is raised. glibc also gives the following error which is not specified in C99 or POSIX.1-2001. Range error: result underflow An underflow floating-point exception (FE_UNDERFLOW) is raised. errno is not set for this case.
VERSIONS
These functions first appeared in glibc in version 2.1.
CONFORMING TO
C99, POSIX.1-2001.
NOTES
This function had to be called "true gamma function" since there is already a function gamma(3) that returns something else (see gamma(3) for details).
BUGS
If x is negative infinity, errno is not set (it should be set to EDOM). In glibc versions 2.3.3 and earlier, an argument of +0 or -0 incorrectly produced a domain error (errno set to EDOM and an FE_INVALID exception raised), rather than a pole error.
SEE ALSO
gamma(3), lgamma(3)
COLOPHON
This page is part of release 3.53 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.
GNU
2010-09-20 TGAMMA(3)
Related Man Pages
tgammaf(3) - centos
tgammal(3) - debian
tgammaf(3) - suse
tgamma(3) - v7
tgamma(3) - plan9
Similar Topics in the Unix Linux Community
Set hard block limit for user using quota
DB2 convert digits to binary format
CentOS7 restoring file capabilities
Unsure why access time on a directory change isn't changing
Please Welcome Dave Munro to the Moderator Team!