# r9ln2r.f

          FUNCTION R9LN2R (X)
    C***BEGIN PROLOGUE  R9LN2R
    ....
    ....
    Warning:   this routine is not intended to be user-callable.
    ....
    ....
    C***SUBSIDIARY
    C***PURPOSE  Evaluate LOG(1+X) from second order relative accuracy so
    C            that LOG(1+X) = X - X**2/2 + X**3*R9LN2R(X).
    C***LIBRARY   SLATEC (FNLIB)
    C***CATEGORY  C4B
    C***TYPE      SINGLE PRECISION (R9LN2R-S, D9LN2R-D, C9LN2R-C)
    C***KEYWORDS  ELEMENTARY FUNCTIONS, FNLIB, LOGARITHM, SECOND ORDER
    C***AUTHOR  Fullerton, W., (LANL)
    C***DESCRIPTION
    C
    C Evaluate  LOG(1+X)  from 2-nd order with relative error accuracy so
    C that    LOG(1+X) = X - X**2/2 + X**3*R9LN2R(X)
    C
    C Series for LN21       on the interval -6.25000D-01 to  0.
    C                                        with weighted error   2.49E-17
    C                                         log weighted error  16.60
    C                               significant figures required  15.87
    C                                    decimal places required  17.31
    C
    C Series for LN22       on the interval  0.          to  8.12500D-01
    C                                        with weighted error   1.42E-17
    C                                         log weighted error  16.85
    C                               significant figures required  15.95
    C                                    decimal places required  17.50
    C
    C***REFERENCES  (NONE)
    C***ROUTINES CALLED  CSEVL, INITS, R1MACH, XERMSG
    C***REVISION HISTORY  (YYMMDD)
    C   780401  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   900720  Routine changed from user-callable to subsidiary.  (WRB)
    C***END PROLOGUE  R9LN2R