jburkardt

ASA245\ Logarithm of Gamma Function {#asa245-logarithm-of-gamma-function align=”center”} ===========================

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ASA245 is a C++ library which evaluates the logarithm of the gamma function.

ASA245 is Applied Statistics Algorithm 245. Source code for many Applied Statistics Algorithms is available through STATLIB.

Licensing: {#licensing align=”center”}

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

Languages: {#languages align=”center”}

ASA245 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: {#related-data-and-programs align=”center”}

FN, a C++ library which approximates elementary and special functions using Chebyshev polynomials, by Wayne Fullerton.

GSL, a C++ library which includes many routines for evaluating special functions.

SLATEC, a FORTRAN90 library which evaluates many special functions.

SPECFUN, a FORTRAN77 library which evaluates certain special functions using fitted data.

TEST_VALUES, a C++ library which contains sample values for a number of distributions.

TOMS291, a C++ library which evaluates the logarithm of the Gamma function.

Reference: {#reference align=”center”}

1. Cornelius Lanczos,\ A precision approximation of the gamma function,\ SIAM Journal on Numerical Analysis, B,\ Volume 1, 1964, pages 86-96.
2. Allan Mcleod,\ Algorithm AS 245: A Robust and Reliable Algorithm for the Logarithm of the Gamma Function,\ Applied Statistics,\ Volume 38, Number 2, 1989, pages 397-402.

Source Code: {#source-code align=”center”}

• asa245.cpp, the source code.
• asa245.hpp, the include file.

Examples and Tests: {#examples-and-tests align=”center”}

• asa245_prb.cpp, a sample calling program.
• asa245_prb_output.txt, the output file.

List of Routines: {#list-of-routines align=”center”}

• ALNGAM computes the logarithm of the gamma function.
• GAMMA_LOG_VALUES returns some values of the Log Gamma function.
• LNGAMMA computes Log(Gamma(X)) using a Lanczos approximation.
• TIMESTAMP prints out the current YMDHMS date as a timestamp.

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

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Last revised on 15 January 2008.