dc/de7/gamr_8f_source.html

 *DECK GAMR

       FUNCTION gamr (X)

 C***BEGIN PROLOGUE  GAMR

 C***PURPOSE  Compute the reciprocal of the Gamma function.

 C***LIBRARY   SLATEC (FNLIB)

 C***CATEGORY  C7A

 C***TYPE      SINGLE PRECISION (GAMR-S, DGAMR-D, CGAMR-C)

 C***KEYWORDS  FNLIB, RECIPROCAL GAMMA FUNCTION, SPECIAL FUNCTIONS

 C***AUTHOR  Fullerton, W., (LANL)

 C***DESCRIPTION

 C

 C GAMR is a single precision function that evaluates the reciprocal

 C of the gamma function for single precision argument X.

 C

 C***REFERENCES  (NONE)

 C***ROUTINES CALLED  ALGAMS, GAMMA, XERCLR, XGETF, XSETF

 C***REVISION HISTORY  (YYMMDD)

 C   770701  DATE WRITTEN

 C   861211  REVISION DATE from Version 3.2

 C   891214  Prologue converted to Version 4.0 format.  (BAB)

 C   900727  Added EXTERNAL statement.  (WRB)

 C***END PROLOGUE  GAMR

       EXTERNAL gamma

 C***FIRST EXECUTABLE STATEMENT  GAMR

       gamr = 0.0

       IF (x.LE.0.0 .AND. aint(x).EQ.x) RETURN

 C

       CALL xgetf(irold)

       CALL xsetf(1)

       IF (abs(x).GT.10.0) go to 10

       gamr = 1.0/gamma(x)

       CALL xerclr

       CALL xsetf(irold)

       RETURN

 C

  10   CALL algams(x, alngx, sgngx)

       CALL xerclr

       CALL xsetf(irold)

       gamr = sgngx * exp(-alngx)

       RETURN

 C

       END

xsetf
subroutine xsetf(KONTRL)
Definition: xsetf.f:2

gamr
function gamr(X)
Definition: gamr.f:2

base_det::exp
int exp(void) const
Definition: DET.h:66

algams
subroutine algams(X, ALGAM, SGNGAM)
Definition: algams.f:2

xgetf
subroutine xgetf(KONTRL)
Definition: xgetf.f:2

to
may be zero for pure relative error test tem the relative tolerance must be greater than or equal to
Definition: Quad-opts.cc:233

abs
OCTAVE_EXPORT octave_value_list return the value of the option it must match the dimension of the state and the relative tolerance must also be a vector of the same length tem it must match the dimension of the state and the absolute tolerance must also be a vector of the same length The local error test applied at each integration step is xample roup abs(local error in x(i))<

xerclr
subroutine xerclr
Definition: xerclr.f:2