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- *DECK DLGAMS
- SUBROUTINE DLGAMS (X, DLGAM, SGNGAM)
- C***BEGIN PROLOGUE DLGAMS
- C***PURPOSE Compute the logarithm of the absolute value of the Gamma
- C function.
- C***LIBRARY SLATEC (FNLIB)
- C***CATEGORY C7A
- C***TYPE DOUBLE PRECISION (ALGAMS-S, DLGAMS-D)
- C***KEYWORDS ABSOLUTE VALUE OF THE LOGARITHM OF THE GAMMA FUNCTION,
- C FNLIB, SPECIAL FUNCTIONS
- C***AUTHOR Fullerton, W., (LANL)
- C***DESCRIPTION
- C
- C DLGAMS(X,DLGAM,SGNGAM) calculates the double precision natural
- C logarithm of the absolute value of the Gamma function for
- C double precision argument X and stores the result in double
- C precision argument DLGAM.
- C
- C***REFERENCES (NONE)
- C***ROUTINES CALLED DLNGAM
- C***REVISION HISTORY (YYMMDD)
- C 770701 DATE WRITTEN
- C 890531 Changed all specific intrinsics to generic. (WRB)
- C 890531 REVISION DATE from Version 3.2
- C 891214 Prologue converted to Version 4.0 format. (BAB)
- C***END PROLOGUE DLGAMS
- DOUBLE PRECISION X, DLGAM, SGNGAM, DLNGAM
- C***FIRST EXECUTABLE STATEMENT DLGAMS
- DLGAM = DLNGAM(X)
- SGNGAM = 1.0D0
- IF (X.GT.0.D0) RETURN
- C
- INT = MOD (-AINT(X), 2.0D0) + 0.1D0
- IF (INT.EQ.0) SGNGAM = -1.0D0
- C
- RETURN
- END
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