dpperm.f

      SUBROUTINE DPPERM (DX, N, IPERM, IER)
C***BEGIN PROLOGUE  DPPERM
C***PURPOSE  Rearrange a given array according to a prescribed
C            permutation vector.
C***LIBRARY   SLATEC
C***CATEGORY  N8
C***TYPE      DOUBLE PRECISION (SPPERM-S, DPPERM-D, IPPERM-I, HPPERM-H)
C***KEYWORDS  PERMUTATION, REARRANGEMENT
C***AUTHOR  McClain, M. A., (NIST)
C           Rhoads, G. S., (NBS)
C***DESCRIPTION
C
C         DPPERM rearranges the data vector DX according to the
C         permutation IPERM: DX(I) <--- DX(IPERM(I)).  IPERM could come
C         from one of the sorting routines IPSORT, SPSORT, DPSORT or
C         HPSORT.
C
C     Description of Parameters
C         DX - input/output -- double precision array of values to be
C                   rearranged.
C         N - input -- number of values in double precision array DX.
C         IPERM - input -- permutation vector.
C         IER - output -- error indicator:
C             =  0  if no error,
C             =  1  if N is zero or negative,
C             =  2  if IPERM is not a valid permutation.
C
C***REFERENCES  (NONE)
C***ROUTINES CALLED  XERMSG
C***REVISION HISTORY  (YYMMDD)
C   901004  DATE WRITTEN
C   920507  Modified by M. McClain to revise prologue text.
C***END PROLOGUE  DPPERM