attflv.f

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C
C
C
  SUBROUTINE attflv(ID,IDQ,IDQQ)
  common/ranseed/nseed
  SAVE  /ranseed/
C
  IF(abs(id).LT.100) THEN
    nsign=1
    idq=id/100
    idqq=-id/10+idq*10
    IF(abs(idq).EQ.3) nsign=-1
    idq=nsign*idq
    idqq=nsign*idqq
    IF(idq.LT.0) THEN
      id0=idq
      idq=idqq
      idqq=id0
    ENDIF
    RETURN
  ENDIF
C   ********return ID of quark(IDQ) and anti-quark(IDQQ)
C     for pions and kaons
c
C Return LU ID for quarks and diquarks for proton(ID=2212) 
C anti-proton(ID=-2212) and nuetron(ID=2112)
C LU ID for d=1,u=2, (ud)0=2101, (ud)1=2103, 
C       (dd)1=1103,(uu)1=2203.
C Use SU(6)  weight  proton=1/3d(uu)1 + 1/6u(ud)1 + 1/2u(ud)0
C       nurtron=1/3u(dd)1 + 1/6d(ud)1 + 1/2d(ud)0
C 
  idq=2
  IF(abs(id).EQ.2112) idq=1
  idqq=2101
  x=atl_ran(nseed)
  IF(x.LE.0.5) go to 30
  IF(x.GT.0.666667) go to 10
  idqq=2103
  go to 30
10  idq=1
  idqq=2203
  IF(abs(id).EQ.2112) THEN
    idq=2
    idqq=1103
  ENDIF
30  IF(id.LT.0) THEN
    id00=idqq
    idqq=-idq
    idq=-id00
  ENDIF
  RETURN
  END