TOMS291
Approximate Log(Gamma(X))

TOMS291 is a C++ program which approximates the logarithm of the Gamma function.

The text of many ACM TOMS algorithms is available online through ACM: http://www.acm.org/pubs/calgo or NETLIB: http://www.netlib.org/toms/index.html.

Licensing:

The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.

Languages:

TOMS291 is available in a C version and a C++ version and a FORTRAN77 version and a FORTRAN90 version and a MATLAB version.

Related Data and Programs:

ASA245, a C++ library which evaluates the logarithm of the Gamma function.

GSL, a C++ library which evaluates many special functions, including the logarithm of the Gamma function.

POLPAK, a C++ library which evaluates a variety of special functions.

SPECFUN, a FORTRAN77 library which evaluates a variety of special functions.

TEST_VALUES, a C++ library which tabulates several values of a variety of special functions.

TOMS708, a FORTRAN90 library which evaluates several special functions, including the logarithm of the Gamma function.

Reference:

1. Malcolm Pike, David Hill,
   Algorithm 291: Logarithm of Gamma Function,
   Communications of the ACM,
   Volume 9, Number 9, September 1966, page 684.

Source Code:

• toms291.cpp, the source code.
• toms291.hpp, the include file.
• toms291.sh, commands to compile the source code.

Examples and Tests:

• toms291_prb.cpp, a sample calling program.
• toms291_prb.sh, commands to compile and run the sample program.
• toms291_prb_output.txt, the output file.

List of Routines:

• ALOGAM computes the logarithm of the Gamma function.
• GAMMA_LOG_VALUES returns some values of the Log Gamma function.
• TIMESTAMP prints out the current YMDHMS date as a timestamp.

You can go up one level to the C++ source codes.