ddawts.f

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      SUBROUTINE ddawts (NEQ, IWT, RTOL, ATOL, Y, WT, RPAR, IPAR)
C***BEGIN PROLOGUE  DDAWTS
C***SUBSIDIARY
C***PURPOSE  Set error weight vector for DDASSL.
C***LIBRARY   SLATEC (DASSL)
C***TYPE      DOUBLE PRECISION (SDAWTS-S, DDAWTS-D)
C***AUTHOR  PETZOLD, LINDA R., (LLNL)
C***DESCRIPTION
C-----------------------------------------------------------------------
C     THIS SUBROUTINE SETS THE ERROR WEIGHT VECTOR
C     WT ACCORDING TO WT(I)=RTOL(I)*ABS(Y(I))+ATOL(I),
C     I=1,-,N.
C     RTOL AND ATOL ARE SCALARS IF IWT = 0,
C     AND VECTORS IF IWT = 1.
C-----------------------------------------------------------------------
C***ROUTINES CALLED  (NONE)
C***REVISION HISTORY  (YYMMDD)
C   830315  DATE WRITTEN
C   901009  Finished conversion to SLATEC 4.0 format (F.N.Fritsch)
C   901019  Merged changes made by C. Ulrich with SLATEC 4.0 format.
C   901026  Added explicit declarations for all variables and minor
C           cosmetic changes to prologue.  (FNF)
C***END PROLOGUE  DDAWTS
C
      INTEGER  neq, iwt, ipar(*)
      DOUBLE PRECISION  rtol(*), atol(*), y(*), wt(*), rpar(*)
C
      INTEGER  i
      DOUBLE PRECISION  atoli, rtoli
C
C***FIRST EXECUTABLE STATEMENT  DDAWTS
      rtoli=rtol(1)
      atoli=atol(1)
      DO 20 i=1,neq
         IF (iwt .EQ.0) go to 10
           rtoli=rtol(i)
           atoli=atol(i)
10         wt(i)=rtoli*abs(y(i))+atoli
20         CONTINUE
      RETURN
C-----------END OF SUBROUTINE DDAWTS------------------------------------
      END