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/* dlgams.f -- translated by f2c (version 20041007).
You must link the resulting object file with libf2c:
on Microsoft Windows system, link with libf2c.lib;
on Linux or Unix systems, link with .../path/to/libf2c.a -lm
or, if you install libf2c.a in a standard place, with -lf2c -lm
-- in that order, at the end of the command line, as in
cc *.o -lf2c -lm
Source for libf2c is in /netlib/f2c/libf2c.zip, e.g.,
http://www.netlib.org/f2c/libf2c.zip
*/
#define V3P_NETLIB_SRC
#include "v3p_netlib.h"
/* Table of constant values */
static doublereal c_b2 = 2.;
/* DECK DLGAMS */
/* Subroutine */ int dlgams_(doublereal *x, doublereal *dlgam, doublereal *
sgngam)
{
/* System generated locals */
doublereal d__1;
/* Builtin functions */
double d_int(doublereal *), d_mod(doublereal *, doublereal *);
/* Local variables */
integer int__;
extern doublereal dlngam_(doublereal *);
/* ***BEGIN PROLOGUE DLGAMS */
/* ***PURPOSE Compute the logarithm of the absolute value of the Gamma */
/* function. */
/* ***LIBRARY SLATEC (FNLIB) */
/* ***CATEGORY C7A */
/* ***TYPE DOUBLE PRECISION (ALGAMS-S, DLGAMS-D) */
/* ***KEYWORDS ABSOLUTE VALUE OF THE LOGARITHM OF THE GAMMA FUNCTION, */
/* FNLIB, SPECIAL FUNCTIONS */
/* ***AUTHOR Fullerton, W., (LANL) */
/* ***DESCRIPTION */
/* DLGAMS(X,DLGAM,SGNGAM) calculates the double precision natural */
/* logarithm of the absolute value of the Gamma function for */
/* double precision argument X and stores the result in double */
/* precision argument DLGAM. */
/* ***REFERENCES (NONE) */
/* ***ROUTINES CALLED DLNGAM */
/* ***REVISION HISTORY (YYMMDD) */
/* 770701 DATE WRITTEN */
/* 890531 Changed all specific intrinsics to generic. (WRB) */
/* 890531 REVISION DATE from Version 3.2 */
/* 891214 Prologue converted to Version 4.0 format. (BAB) */
/* ***END PROLOGUE DLGAMS */
/* ***FIRST EXECUTABLE STATEMENT DLGAMS */
*dlgam = dlngam_(x);
*sgngam = 1.;
if (*x > 0.) {
return 0;
}
d__1 = -d_int(x);
int__ = (integer) (d_mod(&d__1, &c_b2) + .1);
if (int__ == 0) {
*sgngam = -1.;
}
return 0;
} /* dlgams_ */
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