|Routine ID: G106|
|Author(s): K.S. Kölbig||Library: MATHLIB|
|Language: Fortran||Revised: 15.03.1993|
Function subprogram GAMDIS calculates the gamma distribution function (incomplete gamma function)
for real arguments and a > 0.
User Entry Name: GAMDIS
Files Referenced: Unit 6
External References: GAMMA (C302), ALGAMA (C304), MTLMTR (N002), ABEND (Z035)
In any arithmetic expression, GAMDIS(X,A) has the value ,
where GAMDIS, X and A are of type REAL.
The method is described in Ref. 1.
Approximately six digits are correct.
Error G106.2: Difficulties of convergence (unlikely).
The function value is set equal to zero, and a message is written on Unit 6, unless subroutine MTLSET (N002) has been called.
This subprogram is based on a Fortran program for the incomplete gamma functions published in Ref. 2.