datanh.f
DOUBLE PRECISION FUNCTION DATANH (X)
C***BEGIN PROLOGUE DATANH
C***PURPOSE Compute the arc hyperbolic tangent.
C***LIBRARY SLATEC (FNLIB)
C***CATEGORY C4C
C***TYPE DOUBLE PRECISION (ATANH-S, DATANH-D, CATANH-C)
C***KEYWORDS ARC HYPERBOLIC TANGENT, ATANH, ELEMENTARY FUNCTIONS,
C FNLIB, INVERSE HYPERBOLIC TANGENT
C***AUTHOR Fullerton, W., (LANL)
C***DESCRIPTION
C
C DATANH(X) calculates the double precision arc hyperbolic
C tangent for double precision argument X.
C
C Series for ATNH on the interval 0. to 2.50000E-01
C with weighted error 6.86E-32
C log weighted error 31.16
C significant figures required 30.00
C decimal places required 31.88
C
C***REFERENCES (NONE)
C***ROUTINES CALLED D1MACH, DCSEVL, INITDS, XERMSG
C***REVISION HISTORY (YYMMDD)
C 770601 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 900315 CALLs to XERROR changed to CALLs to XERMSG. (THJ)
C***END PROLOGUE DATANH