hijing/src/pyhikmap.f

0001
0002 C*********************************************************************
0003
0004       SUBROUTINE PYHIKMAP(IVAR,MVAR,VVAR)
0005
0006 C...Maps a uniform distribution into a distribution of a kinematical
0007 C...variable according to one of the possibilities allowed. It is
0008 C...assumed that kinematical limits have been set by a PYKLIM call.
0009       COMMON/LUDAT2/KCHG(500,3),PMAS(500,4),PARF(2000),VCKM(4,4)
0010       SAVE /LUDAT2/
0011       COMMON/PYHIINT1/MINT(400),VINT(400)
0012       SAVE /PYHIINT1/
0013       COMMON/PYHIINT2/ISET(200),KFPR(200,2),COEF(200,20),ICOL(40,4,2)
0014       SAVE /PYHIINT2/
0015
0016 C...Convert VVAR to tau variable.
0017       ISUB=MINT(1)
0018       IF(IVAR.EQ.1) THEN
0019         TAUMIN=VINT(11)
0020         TAUMAX=VINT(31)
0021         IF(MVAR.EQ.3.OR.MVAR.EQ.4) THEN
0022           TAURE=VINT(73)
0023           GAMRE=VINT(74)
0024         ELSEIF(MVAR.EQ.5.OR.MVAR.EQ.6) THEN
0025           TAURE=VINT(75)
0026           GAMRE=VINT(76)
0027         ENDIF
0028         IF(MINT(43).EQ.1.AND.(ISET(ISUB).EQ.1.OR.ISET(ISUB).EQ.2)) THEN
0029           TAU=1.
0030         ELSEIF(MVAR.EQ.1) THEN
0031           TAU=TAUMIN*(TAUMAX/TAUMIN)**VVAR
0032         ELSEIF(MVAR.EQ.2) THEN
0033           TAU=TAUMAX*TAUMIN/(TAUMIN+(TAUMAX-TAUMIN)*VVAR)
0034         ELSEIF(MVAR.EQ.3.OR.MVAR.EQ.5) THEN
0035           RATGEN=(TAURE+TAUMAX)/(TAURE+TAUMIN)*TAUMIN/TAUMAX
0036           TAU=TAURE*TAUMIN/((TAURE+TAUMIN)*RATGEN**VVAR-TAUMIN)
0037         ELSE
0038           AUPP=ATAN((TAUMAX-TAURE)/GAMRE)
0039           ALOW=ATAN((TAUMIN-TAURE)/GAMRE)
0040           TAU=TAURE+GAMRE*TAN(ALOW+(AUPP-ALOW)*VVAR)
0041         ENDIF
0042         VINT(21)=MIN(TAUMAX,MAX(TAUMIN,TAU))
0043
0044 C...Convert VVAR to y* variable.
0045       ELSEIF(IVAR.EQ.2) THEN
0046         YSTMIN=VINT(12)
0047         YSTMAX=VINT(32)
0048         IF(MINT(43).EQ.1) THEN
0049           YST=0.
0050         ELSEIF(MINT(43).EQ.2) THEN
0051           IF(ISET(ISUB).LE.2) YST=-0.5*LOG(VINT(21))
0052           IF(ISET(ISUB).GE.3) YST=-0.5*LOG(VINT(26))
0053         ELSEIF(MINT(43).EQ.3) THEN
0054           IF(ISET(ISUB).LE.2) YST=0.5*LOG(VINT(21))
0055           IF(ISET(ISUB).GE.3) YST=0.5*LOG(VINT(26))
0056         ELSEIF(MVAR.EQ.1) THEN
0057           YST=YSTMIN+(YSTMAX-YSTMIN)*SQRT(VVAR)
0058         ELSEIF(MVAR.EQ.2) THEN
0059           YST=YSTMAX-(YSTMAX-YSTMIN)*SQRT(1.-VVAR)
0060         ELSE
0061           AUPP=ATAN(EXP(YSTMAX))
0062           ALOW=ATAN(EXP(YSTMIN))
0063           YST=LOG(TAN(ALOW+(AUPP-ALOW)*VVAR))
0064         ENDIF
0065         VINT(22)=MIN(YSTMAX,MAX(YSTMIN,YST))
0066
0067 C...Convert VVAR to cos(theta-hat) variable.
0068       ELSEIF(IVAR.EQ.3) THEN
0069         RM34=2.*VINT(63)*VINT(64)/(VINT(21)*VINT(2))**2
0070         RSQM=1.+RM34
0071         IF(2.*VINT(71)**2/(VINT(21)*VINT(2)).LT.0.0001) RM34=MAX(RM34,
0072      &  2.*VINT(71)**2/(VINT(21)*VINT(2)))
0073         CTNMIN=VINT(13)
0074         CTNMAX=VINT(33)
0075         CTPMIN=VINT(14)
0076         CTPMAX=VINT(34)
0077         IF(MVAR.EQ.1) THEN
0078           ANEG=CTNMAX-CTNMIN
0079           APOS=CTPMAX-CTPMIN
0080           IF(ANEG.GT.0..AND.VVAR*(ANEG+APOS).LE.ANEG) THEN
0081             VCTN=VVAR*(ANEG+APOS)/ANEG
0082             CTH=CTNMIN+(CTNMAX-CTNMIN)*VCTN
0083           ELSE
0084             VCTP=(VVAR*(ANEG+APOS)-ANEG)/APOS
0085             CTH=CTPMIN+(CTPMAX-CTPMIN)*VCTP
0086           ENDIF
0087         ELSEIF(MVAR.EQ.2) THEN
0088           RMNMIN=MAX(RM34,RSQM-CTNMIN)
0089           RMNMAX=MAX(RM34,RSQM-CTNMAX)
0090           RMPMIN=MAX(RM34,RSQM-CTPMIN)
0091           RMPMAX=MAX(RM34,RSQM-CTPMAX)
0092           ANEG=LOG(RMNMIN/RMNMAX)
0093           APOS=LOG(RMPMIN/RMPMAX)
0094           IF(ANEG.GT.0..AND.VVAR*(ANEG+APOS).LE.ANEG) THEN
0095             VCTN=VVAR*(ANEG+APOS)/ANEG
0096             CTH=RSQM-RMNMIN*(RMNMAX/RMNMIN)**VCTN
0097           ELSE
0098             VCTP=(VVAR*(ANEG+APOS)-ANEG)/APOS
0099             CTH=RSQM-RMPMIN*(RMPMAX/RMPMIN)**VCTP
0100           ENDIF
0101         ELSEIF(MVAR.EQ.3) THEN
0102           RMNMIN=MAX(RM34,RSQM+CTNMIN)
0103           RMNMAX=MAX(RM34,RSQM+CTNMAX)
0104           RMPMIN=MAX(RM34,RSQM+CTPMIN)
0105           RMPMAX=MAX(RM34,RSQM+CTPMAX)
0106           ANEG=LOG(RMNMAX/RMNMIN)
0107           APOS=LOG(RMPMAX/RMPMIN)
0108           IF(ANEG.GT.0..AND.VVAR*(ANEG+APOS).LE.ANEG) THEN
0109             VCTN=VVAR*(ANEG+APOS)/ANEG
0110             CTH=RMNMIN*(RMNMAX/RMNMIN)**VCTN-RSQM
0111           ELSE
0112             VCTP=(VVAR*(ANEG+APOS)-ANEG)/APOS
0113             CTH=RMPMIN*(RMPMAX/RMPMIN)**VCTP-RSQM
0114           ENDIF
0115         ELSEIF(MVAR.EQ.4) THEN
0116           RMNMIN=MAX(RM34,RSQM-CTNMIN)
0117           RMNMAX=MAX(RM34,RSQM-CTNMAX)
0118           RMPMIN=MAX(RM34,RSQM-CTPMIN)
0119           RMPMAX=MAX(RM34,RSQM-CTPMAX)
0120           ANEG=1./RMNMAX-1./RMNMIN
0121           APOS=1./RMPMAX-1./RMPMIN
0122           IF(ANEG.GT.0..AND.VVAR*(ANEG+APOS).LE.ANEG) THEN
0123             VCTN=VVAR*(ANEG+APOS)/ANEG
0124             CTH=RSQM-1./(1./RMNMIN+ANEG*VCTN)
0125           ELSE
0126             VCTP=(VVAR*(ANEG+APOS)-ANEG)/APOS
0127             CTH=RSQM-1./(1./RMPMIN+APOS*VCTP)
0128           ENDIF
0129         ELSEIF(MVAR.EQ.5) THEN
0130           RMNMIN=MAX(RM34,RSQM+CTNMIN)
0131           RMNMAX=MAX(RM34,RSQM+CTNMAX)
0132           RMPMIN=MAX(RM34,RSQM+CTPMIN)
0133           RMPMAX=MAX(RM34,RSQM+CTPMAX)
0134           ANEG=1./RMNMIN-1./RMNMAX
0135           APOS=1./RMPMIN-1./RMPMAX
0136           IF(ANEG.GT.0..AND.VVAR*(ANEG+APOS).LE.ANEG) THEN
0137             VCTN=VVAR*(ANEG+APOS)/ANEG
0138             CTH=1./(1./RMNMIN-ANEG*VCTN)-RSQM
0139           ELSE
0140             VCTP=(VVAR*(ANEG+APOS)-ANEG)/APOS
0141             CTH=1./(1./RMPMIN-APOS*VCTP)-RSQM
0142           ENDIF
0143         ENDIF
0144         IF(CTH.LT.0.) CTH=MIN(CTNMAX,MAX(CTNMIN,CTH))
0145         IF(CTH.GT.0.) CTH=MIN(CTPMAX,MAX(CTPMIN,CTH))
0146         VINT(23)=CTH
0147
0148 C...Convert VVAR to tau' variable.
0149       ELSEIF(IVAR.EQ.4) THEN
0150         TAU=VINT(11)
0151         TAUPMN=VINT(16)
0152         TAUPMX=VINT(36)
0153         IF(MINT(43).EQ.1) THEN
0154           TAUP=1.
0155         ELSEIF(MVAR.EQ.1) THEN
0156           TAUP=TAUPMN*(TAUPMX/TAUPMN)**VVAR
0157         ELSE
0158           AUPP=(1.-TAU/TAUPMX)**4
0159           ALOW=(1.-TAU/TAUPMN)**4
0160           TAUP=TAU/(1.-(ALOW+(AUPP-ALOW)*VVAR)**0.25)
0161         ENDIF
0162         VINT(26)=MIN(TAUPMX,MAX(TAUPMN,TAUP))
0163       ENDIF
0164
0165       RETURN
0166       END