TEvtGen/PHOTOS/phooma.F

   1       SUBROUTINE PHOOMA(IFIRST,ILAST,POINTR)
   2 C.----------------------------------------------------------------------
   3 C.
   4 C.    PHOTOS:   PHOton radiation in decays Order MAss vector
   5 C.
   6 C.    Purpose:  Order  the  contents  of array 'POINTR' according to the
   7 C.              decreasing value in the array 'MASS'.
   8 C.
   9 C.    Input Parameters:  IFIRST, ILAST:  Pointers  to  the  vector loca-
  10 C.                                       tion be sorted,
  11 C.                       POINTR:         Unsorted array with pointers to
  12 C.                                       /PHOEVT/.
  13 C.
  14 C.    Output Parameter:  POINTR:         Sorted arrays  with  respect to
  15 C.                                       particle mass 'PPHO(5,*)'.
  16 C.
  17 C.    Author(s):  B. van Eijk                     Created at:  28/11/89
  18 C.                                                Last Update: 27/05/93
  19 C.
  20 C.----------------------------------------------------------------------
  21       IMPLICIT NONE
  22       INTEGER NMXPHO
  23       PARAMETER (NMXPHO=10000)
  24       INTEGER IDPHO,ISTPHO,JDAPHO,JMOPHO,NEVPHO,NPHO
  25       REAL*8 PPHO,VPHO
  26       COMMON/PHOEVT/NEVPHO,NPHO,ISTPHO(NMXPHO),IDPHO(NMXPHO),
  27      &JMOPHO(2,NMXPHO),JDAPHO(2,NMXPHO),PPHO(5,NMXPHO),VPHO(4,NMXPHO)
  28       INTEGER IFIRST,ILAST,I,J,BUFPOI,POINTR(NMXPHO)
  29       REAL*8 BUFMAS,MASS(NMXPHO)
  30       IF (IFIRST.EQ.ILAST) RETURN
  31 C--
  32 C--   Copy particle masses
  33       DO 10 I=IFIRST,ILAST
  34    10 MASS(I)=PPHO(5,POINTR(I))
  35 C--
  36 C--   Order the masses in a decreasing series
  37       DO 30 I=IFIRST,ILAST-1
  38         DO 20 J=I+1,ILAST
  39           IF (MASS(J).LE.MASS(I)) GOTO 20
  40           BUFPOI=POINTR(J)
  41           POINTR(J)=POINTR(I)
  42           POINTR(I)=BUFPOI
  43           BUFMAS=MASS(J)
  44           MASS(J)=MASS(I)
  45           MASS(I)=BUFMAS
  46    20   CONTINUE
  47    30 CONTINUE
  48       RETURN
  49       END