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