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|
SUBROUTINE SBORN(P,ANS_SUMMED)
C
C Generated by MadGraph5_aMC@NLO v. %(version)s, %(date)s
C By the MadGraph5_aMC@NLO Development Team
C Visit launchpad.net/madgraph5 and amcatnlo.web.cern.ch
C
C
C Return the sum of the split orders which are required in
C orders.inc (BORN_ORDERS)
C Also the values needed for the counterterms are stored in the
C C_BORN_CNT common block
C
C
C Process: d~ u > w+ [ all = QED QCD ] QCD^2<=2 QED^2<=2
C Process: s~ c > w+ [ all = QED QCD ] QCD^2<=2 QED^2<=2
C
C
C CONSTANTS
C
IMPLICIT NONE
INCLUDE 'nexternal.inc'
INTEGER NAMPSO, NSQAMPSO
PARAMETER (NAMPSO=1, NSQAMPSO=1)
INTEGER NGRAPHS
PARAMETER (NGRAPHS= 1)
C
C ARGUMENTS
C
REAL*8 P(0:3,NEXTERNAL-1)
C
C VARIABLES
C
INTEGER I,J,K
INCLUDE 'orders.inc'
DOUBLE PRECISION ANS_SUMMED
COMPLEX*16 ANS(2,0:NSQAMPSO), ANS_CNT(2, NSPLITORDERS)
LOGICAL KEEP_ORDER(NSQAMPSO), KEEP_ORDER_CNT(NSPLITORDERS,
$ NSQAMPSO), FIRSTTIME
DATA KEEP_ORDER / NSQAMPSO * .TRUE. /
COMMON /C_KEEP_ORDER_CNT/ KEEP_ORDER_CNT
COMMON /C_BORN_CNT/ ANS_CNT
INTEGER ORD_SUBTRACT
DATA FIRSTTIME / .TRUE. /
INTEGER AMP_ORDERS(NSPLITORDERS)
DOUBLE PRECISION TINY
PARAMETER (TINY = 1D-12)
DOUBLE PRECISION MAX_VAL
DOUBLE PRECISION WGT_ME_BORN,WGT_ME_REAL
COMMON /C_WGT_ME_TREE/ WGT_ME_BORN,WGT_ME_REAL
DOUBLE PRECISION AMP2B(1), JAMP2B(0:1,0:NAMPSO)
COMMON/TO_AMPS_BORN/ AMP2B, JAMP2B
DOUBLE PRECISION AMP2(1), JAMP2(0:1)
COMMON/TO_AMPS/ AMP2, JAMP2
LOGICAL SPLIT_TYPE_USED(NSPLITORDERS)
COMMON/TO_SPLIT_TYPE_USED/SPLIT_TYPE_USED
C
C FUNCTIONS
C
INTEGER GETORDPOWFROMINDEX_B
INTEGER ORDERS_TO_AMP_SPLIT_POS
C
C BEGIN CODE
C
C look for orders which match the born order constraint
IF (FIRSTTIME) THEN
DO I = 1, NSQAMPSO
C this is for the orders of the born to integrate
DO J = 1, NSPLITORDERS
IF(GETORDPOWFROMINDEX_B(J, I) .GT. BORN_ORDERS(J)) THEN
KEEP_ORDER(I) = .FALSE.
EXIT
ENDIF
ENDDO
C this is for the orders of the counterterms
DO J = 1, NSPLITORDERS
KEEP_ORDER_CNT(J,I) = .TRUE.
DO K = 1, NSPLITORDERS
IF (J.EQ.K) THEN
ORD_SUBTRACT=2
ELSE
ORD_SUBTRACT=0
ENDIF
IF(GETORDPOWFROMINDEX_B(K, I) .GT. NLO_ORDERS(K)
$ -ORD_SUBTRACT) THEN
KEEP_ORDER_CNT(J,I) = .FALSE.
EXIT
ENDIF
ENDDO
ENDDO
IF (KEEP_ORDER(I)) THEN
WRITE(*,*) 'BORN: keeping split order ', I
ELSE
WRITE(*,*) 'BORN: not keeping split order ', I
ENDIF
ENDDO
DO J = 1, NSPLITORDERS
WRITE(*,*) 'counterterm S.O', J, ORDERNAMES(J)
DO I = 1, NSQAMPSO
IF (KEEP_ORDER_CNT(J,I)) THEN
WRITE(*,*) 'BORN: keeping split order', I
ELSE
WRITE(*,*) 'BORN: not keeping split order', I
ENDIF
ENDDO
ENDDO
FIRSTTIME = .FALSE.
ENDIF
CALL SBORN_SPLITORDERS(P,ANS)
C the born to be integrated
ANS_SUMMED = 0D0
MAX_VAL = 0D0
C reset the amp_split array
AMP_SPLIT(1:AMP_SPLIT_SIZE) = 0D0
AMP_SPLIT_CNT(1:AMP_SPLIT_SIZE,1:2,1:NSPLITORDERS) = DCMPLX(0D0
$ ,0D0)
DO I = 1, NSQAMPSO
MAX_VAL = MAX(MAX_VAL, ABS(ANS(1,I)))
ENDDO
DO I = 1, NSQAMPSO
IF (KEEP_ORDER(I)) THEN
ANS_SUMMED = ANS_SUMMED + ANS(1,I)
C keep track of the separate pieces correspoinding to
C different coupling combinations
DO J = 1, NSPLITORDERS
AMP_ORDERS(J) = GETORDPOWFROMINDEX_B(J, I)
ENDDO
IF(ABS(ANS(1,I)).GT.MAX_VAL*TINY)
$ AMP_SPLIT(ORDERS_TO_AMP_SPLIT_POS(AMP_ORDERS)) = ANS(1,I)
ENDIF
ENDDO
C this is to avoid fake non-zero contributions
IF (ABS(ANS_SUMMED).LT.MAX_VAL*TINY) ANS_SUMMED=0D0
WGT_ME_BORN=ANS_SUMMED
C fill the amp2 and jamp2 arrays
AMP2(1:NGRAPHS)=AMP2B(1:NGRAPHS) ! amp2 just needs to be copyed
DO I = 0, INT(JAMP2B(0,0))
JAMP2(I)=0D0
DO J = 1, NAMPSO
C here sum all, this may be refined later
JAMP2(I)=JAMP2(I)+JAMP2B(I,J)
ENDDO
ENDDO
C quantities for the counterterms
DO J = 1, NSPLITORDERS
ANS_CNT(1:2,J) = (0D0, 0D0)
IF (.NOT.SPLIT_TYPE_USED(J)) CYCLE
DO I = 1, NSQAMPSO
IF (KEEP_ORDER_CNT(J,I)) THEN
ANS_CNT(1,J) = ANS_CNT(1,J) + ANS(1,I)
ANS_CNT(2,J) = ANS_CNT(2,J) + ANS(2,I)
C keep track of the separate pieces also for counterterms
DO K = 1, NSPLITORDERS
AMP_ORDERS(K) = GETORDPOWFROMINDEX_B(K, I)
C take into account the fact that the counterterm for a
C given split order
C will be multiplied by the corresponding squared coupling
IF (K.EQ.J) AMP_ORDERS(K) = AMP_ORDERS(K) + 2
ENDDO
C this is to avoid fake non-zero contributions
IF (ABS(ANS(1,I)).GT.MAX_VAL*TINY)
$ AMP_SPLIT_CNT(ORDERS_TO_AMP_SPLIT_POS(AMP_ORDERS),1,J) =
$ ANS(1,I)
IF (ABS(ANS(2,I)).GT.MAX_VAL*TINY)
$ AMP_SPLIT_CNT(ORDERS_TO_AMP_SPLIT_POS(AMP_ORDERS),2,J) =
$ ANS(2,I)
ENDIF
ENDDO
C this is to avoid fake non-zero contributions
IF (ABS(ANS_CNT(1,J)).LT.MAX_VAL*TINY) ANS_CNT(1,J)=(0D0,0D0)
IF (ABS(ANS_CNT(2,J)).LT.MAX_VAL*TINY) ANS_CNT(2,J)=(0D0,0D0)
ENDDO
999 RETURN
END
SUBROUTINE SBORN_SPLITORDERS(P1,ANS)
C
C Generated by MadGraph5_aMC@NLO v. %(version)s, %(date)s
C By the MadGraph5_aMC@NLO Development Team
C Visit launchpad.net/madgraph5 and amcatnlo.web.cern.ch
C
C RETURNS AMPLITUDE SQUARED SUMMED/AVG OVER COLORS
C AND HELICITIES
C FOR THE POINT IN PHASE SPACE P1(0:3,NEXTERNAL-1)
C
C Process: d~ u > w+ [ all = QED QCD ] QCD^2<=2 QED^2<=2
C Process: s~ c > w+ [ all = QED QCD ] QCD^2<=2 QED^2<=2
C
IMPLICIT NONE
C
C CONSTANTS
C
INCLUDE 'nexternal.inc'
INCLUDE 'born_nhel.inc'
INTEGER NCOMB
PARAMETER ( NCOMB= 12 )
INTEGER NAMPSO, NSQAMPSO
PARAMETER (NAMPSO=1, NSQAMPSO=1)
INTEGER THEL
PARAMETER (THEL=NCOMB*4)
INTEGER NGRAPHS
PARAMETER (NGRAPHS= 1)
C
C ARGUMENTS
C
REAL*8 P1(0:3,NEXTERNAL-1)
COMPLEX*16 ANS(2,0:NSQAMPSO)
C
C LOCAL VARIABLES
C
INTEGER IHEL,IDEN,I,J,JJ,GLU_IJ
REAL*8 BORNS(2,0:NSQAMPSO)
COMPLEX*16 BORNTILDE
INTEGER NTRY(4)
DATA NTRY /4*0/
COMPLEX*16 T(2,NSQAMPSO)
INTEGER NHEL(NEXTERNAL-1,NCOMB)
DATA (NHEL(I, 1),I=1,3) /-1, 1,-1/
DATA (NHEL(I, 2),I=1,3) /-1, 1, 0/
DATA (NHEL(I, 3),I=1,3) /-1, 1, 1/
DATA (NHEL(I, 4),I=1,3) /-1,-1,-1/
DATA (NHEL(I, 5),I=1,3) /-1,-1, 0/
DATA (NHEL(I, 6),I=1,3) /-1,-1, 1/
DATA (NHEL(I, 7),I=1,3) / 1, 1,-1/
DATA (NHEL(I, 8),I=1,3) / 1, 1, 0/
DATA (NHEL(I, 9),I=1,3) / 1, 1, 1/
DATA (NHEL(I, 10),I=1,3) / 1,-1,-1/
DATA (NHEL(I, 11),I=1,3) / 1,-1, 0/
DATA (NHEL(I, 12),I=1,3) / 1,-1, 1/
INTEGER IDEN_VALUES(4)
DATA IDEN_VALUES /36, 36, 36, 36/
INTEGER IJ_VALUES(4)
DATA IJ_VALUES /1, 2, 1, 2/
C
C GLOBAL VARIABLES
C
DOUBLE PRECISION AMP2(NGRAPHS), JAMP2(0:1,0:NAMPSO)
COMMON/TO_AMPS_BORN/ AMP2, JAMP2
DATA JAMP2(0,0) / 1/
LOGICAL GOODHEL(NCOMB,4)
COMMON /C_GOODHEL/GOODHEL
DOUBLE COMPLEX SAVEAMP(NGRAPHS,MAX_BHEL)
COMMON/TO_SAVEAMP/SAVEAMP
DOUBLE PRECISION SAVEMOM(NEXTERNAL-1,2)
COMMON/TO_SAVEMOM/SAVEMOM
DOUBLE PRECISION HEL_FAC
INTEGER GET_HEL,SKIP(4)
COMMON/CBORN/HEL_FAC,GET_HEL,SKIP
LOGICAL CALCULATEDBORN
COMMON/CCALCULATEDBORN/CALCULATEDBORN
INTEGER NFKSPROCESS
COMMON/C_NFKSPROCESS/NFKSPROCESS
LOGICAL COND_IJ
C ----------
C BEGIN CODE
C ----------
IDEN=IDEN_VALUES(NFKSPROCESS)
GLU_IJ = IJ_VALUES(NFKSPROCESS)
NTRY(NFKSPROCESS)=NTRY(NFKSPROCESS)+1
IF (NTRY(NFKSPROCESS).LT.2) THEN
IF (GLU_IJ.EQ.0) THEN
SKIP(NFKSPROCESS)=0
ELSE
SKIP(NFKSPROCESS)=1
DO WHILE(NHEL(GLU_IJ ,SKIP(NFKSPROCESS)).NE.-NHEL(GLU_IJ ,1))
SKIP(NFKSPROCESS)=SKIP(NFKSPROCESS)+1
ENDDO
SKIP(NFKSPROCESS)=SKIP(NFKSPROCESS)-1
ENDIF
ENDIF
DO JJ=1,NGRAPHS
AMP2(JJ)=0D0
ENDDO
DO I=0,NAMPSO
DO JJ=1,INT(JAMP2(0,0))
JAMP2(JJ,I)=0D0
ENDDO
ENDDO
IF (CALCULATEDBORN) THEN
DO J=1,NEXTERNAL-1
IF (SAVEMOM(J,1).NE.P1(0,J) .OR. SAVEMOM(J,2).NE.P1(3,J))
$ THEN
CALCULATEDBORN=.FALSE.
WRITE (*,*) 'momenta not the same in Born'
STOP
ENDIF
ENDDO
ENDIF
IF (.NOT.CALCULATEDBORN) THEN
DO J=1,NEXTERNAL-1
SAVEMOM(J,1)=P1(0,J)
SAVEMOM(J,2)=P1(3,J)
ENDDO
DO J=1,MAX_BHEL
DO JJ=1,NGRAPHS
SAVEAMP(JJ,J)=(0D0,0D0)
ENDDO
ENDDO
ENDIF
DO I=0,NSQAMPSO
ANS(1,I) = 0D0
ANS(2,I) = 0D0
ENDDO
HEL_FAC=1D0
DO IHEL=1,NCOMB
! the following lines are to avoid segfaults when glu_ij=0
COND_IJ=SKIP(NFKSPROCESS).EQ.0
IF (.NOT.COND_IJ) COND_IJ=COND_IJ.OR.NHEL(GLU_IJ,IHEL)
$ .EQ.NHEL(GLU_IJ,1)
!if (nhel(glu_ij,ihel).EQ.NHEL(GLU_IJ,1).or.skip(nfksprocess).eq.0) then
IF (COND_IJ) THEN
IF ((GOODHEL(IHEL,NFKSPROCESS) .OR. GOODHEL(IHEL
$ +SKIP(NFKSPROCESS),NFKSPROCESS) .OR. NTRY(NFKSPROCESS) .LT.
$ 2) ) THEN
CALL BORN(P1,NHEL(1,IHEL),IHEL,T,BORNS)
DO I=1,NSQAMPSO
ANS(1,I)=ANS(1,I)+T(1,I)
ANS(2,I)=ANS(2,I)+T(2,I)
ENDDO
IF ( BORNS(1,0).NE.0D0 .AND. .NOT. GOODHEL(IHEL
$ ,NFKSPROCESS) ) THEN
GOODHEL(IHEL,NFKSPROCESS)=.TRUE.
ENDIF
IF ( BORNS(2,0).NE.0D0 .AND. .NOT. GOODHEL(IHEL
$ +SKIP(NFKSPROCESS),NFKSPROCESS) ) THEN
GOODHEL(IHEL+SKIP(NFKSPROCESS),NFKSPROCESS)=.TRUE.
ENDIF
ENDIF
ENDIF
ENDDO
DO I=1,NSQAMPSO
ANS(1,I)=ANS(1,I)/DBLE(IDEN)
ANS(2,I)=ANS(2,I)/DBLE(IDEN)
ANS(1,0)=ANS(1,0)+ANS(1,I)
ANS(2,0)=ANS(2,0)+ANS(2,I)
ENDDO
CALCULATEDBORN=.TRUE.
END
SUBROUTINE BORN(P,NHEL,HELL,ANS,BORNS)
C
C Generated by MadGraph5_aMC@NLO v. %(version)s, %(date)s
C By the MadGraph5_aMC@NLO Development Team
C Visit launchpad.net/madgraph5 and amcatnlo.web.cern.ch
C RETURNS AMPLITUDE SQUARED SUMMED/AVG OVER COLORS
C FOR THE POINT WITH EXTERNAL LINES W(0:6,NEXTERNAL-1)
C Process: d~ u > w+ [ all = QED QCD ] QCD^2<=2 QED^2<=2
C Process: s~ c > w+ [ all = QED QCD ] QCD^2<=2 QED^2<=2
C
IMPLICIT NONE
C
C CONSTANTS
C
INTEGER NAMPSO, NSQAMPSO
PARAMETER (NAMPSO=1, NSQAMPSO=1)
INTEGER NGRAPHS, NEIGEN
PARAMETER (NGRAPHS= 1,NEIGEN= 1)
INTEGER NWAVEFUNCS, NCOLOR
PARAMETER (NWAVEFUNCS=3, NCOLOR=1)
REAL*8 ZERO
PARAMETER (ZERO=0D0)
COMPLEX*16 IMAG1
PARAMETER (IMAG1 = (0D0,1D0))
INCLUDE 'nexternal.inc'
INCLUDE 'born_nhel.inc'
INCLUDE 'coupl.inc'
C
C ARGUMENTS
C
REAL*8 P(0:3,NEXTERNAL-1),BORNS(2,0:NSQAMPSO)
INTEGER NHEL(NEXTERNAL-1), HELL
COMPLEX*16 ANS(2,NSQAMPSO)
C
C LOCAL VARIABLES
C
INTEGER I,J,M,N,IHEL,BACK_HEL,GLU_IJ
INTEGER IC(NEXTERNAL-1),NMO
PARAMETER (NMO=NEXTERNAL-1)
DATA IC /NMO*1/
REAL*8 DENOM(NCOLOR), CF(NCOLOR,NCOLOR)
COMPLEX*16 ZTEMP, AMP(NGRAPHS), JAMP(NCOLOR,NAMPSO), W(8
$ ,NWAVEFUNCS), JAMPH(2, NCOLOR,NAMPSO)
C
C GLOBAL VARIABLES
C
DOUBLE PRECISION AMP2(1), JAMP2(0:1,0:NAMPSO)
COMMON/TO_AMPS_BORN/ AMP2, JAMP2
DOUBLE COMPLEX SAVEAMP(NGRAPHS,MAX_BHEL)
COMMON/TO_SAVEAMP/SAVEAMP
DOUBLE PRECISION HEL_FAC
INTEGER GET_HEL,SKIP(4)
COMMON/CBORN/HEL_FAC,GET_HEL,SKIP
LOGICAL CALCULATEDBORN
COMMON/CCALCULATEDBORN/CALCULATEDBORN
INTEGER NFKSPROCESS
COMMON/C_NFKSPROCESS/NFKSPROCESS
INTEGER STEP_HEL
LOGICAL COND_IJ
C
C FUNCTION
C
INTEGER SQSOINDEXB
INTEGER IJ_VALUES(4)
DATA IJ_VALUES /1, 2, 1, 2/
C
C COLOR DATA
C
DATA DENOM(1)/1/
DATA (CF(I, 1),I= 1, 1) / 3/
C 1 T(1,2)
C ----------
C BEGIN CODE
C ----------
GLU_IJ = IJ_VALUES(NFKSPROCESS)
DO I = 1, NSQAMPSO
ANS(1,I)=0D0
ANS(2,I)=0D0
BORNS(1,I)=0D0
BORNS(2,I)=0D0
ENDDO
BORNS(1,0)=0D0
BORNS(2,0)=0D0
IF (GLU_IJ.NE.0) THEN
BACK_HEL = NHEL(GLU_IJ)
IF (BACK_HEL.NE.0) THEN
STEP_HEL=-2*BACK_HEL
ELSE
STEP_HEL=1
ENDIF
ELSE
BACK_HEL=0
STEP_HEL=1
ENDIF
DO IHEL=BACK_HEL,-BACK_HEL,STEP_HEL
IF (GLU_IJ.NE.0) THEN
COND_IJ=IHEL.EQ.BACK_HEL.OR.NHEL(GLU_IJ).NE.0
ELSE
COND_IJ=IHEL.EQ.BACK_HEL
ENDIF
IF (COND_IJ) THEN
IF (GLU_IJ.NE.0) THEN
IF (NHEL(GLU_IJ).NE.0) NHEL(GLU_IJ) = IHEL
ENDIF
IF (.NOT. CALCULATEDBORN) THEN
CALL OXXXXX(P(0,1),ZERO,NHEL(1),-1*IC(1),W(1,1))
CALL IXXXXX(P(0,2),ZERO,NHEL(2),+1*IC(2),W(1,2))
CALL VXXXXX(P(0,3),MDL_MW,NHEL(3),+1*IC(3),W(1,3))
C Amplitude(s) for diagram number 1
CALL FFV2_0(W(1,2),W(1,1),W(1,3),GC_47,AMP(1))
DO I=1,NGRAPHS
IF(IHEL.EQ.BACK_HEL)THEN
SAVEAMP(I,HELL)=AMP(I)
ELSEIF(IHEL.EQ.-BACK_HEL)THEN
SAVEAMP(I,HELL+SKIP(NFKSPROCESS))=AMP(I)
ELSE
WRITE(*,*) 'ERROR #1 in born.f'
STOP
ENDIF
ENDDO
ELSEIF (CALCULATEDBORN) THEN
DO I=1,NGRAPHS
IF(IHEL.EQ.BACK_HEL)THEN
AMP(I)=SAVEAMP(I,HELL)
ELSEIF(IHEL.EQ.-BACK_HEL)THEN
AMP(I)=SAVEAMP(I,HELL+SKIP(NFKSPROCESS))
ELSE
WRITE(*,*) 'ERROR #1 in born.f'
STOP
ENDIF
ENDDO
ENDIF
C JAMPs contributing to orders QCD=0 QED=1
JAMP(1,1)=-AMP(1)
DO M = 1, NAMPSO
DO I = 1, NCOLOR
ZTEMP = (0.D0,0.D0)
DO J = 1, NCOLOR
ZTEMP = ZTEMP + CF(J,I)*JAMP(J,M)
ENDDO
DO N = 1, NAMPSO
BORNS(2-(1+BACK_HEL*IHEL)/2,SQSOINDEXB(M,N))=BORNS(2
$ -(1+BACK_HEL*IHEL)/2,SQSOINDEXB(M,N))+ZTEMP
$ *DCONJG(JAMP(I,N))/DENOM(I)
ENDDO
ENDDO
ENDDO
DO I = 1, NGRAPHS
AMP2(I)=AMP2(I)+AMP(I)*DCONJG(AMP(I))
ENDDO
DO J = 1,NAMPSO
DO I = 1, NCOLOR
JAMP2(I,J)=JAMP2(I,J)+JAMP(I,J)*DCONJG(JAMP(I,J))
JAMPH(2-(1+BACK_HEL*IHEL)/2,I,J)=JAMP(I,J)
ENDDO
ENDDO
ENDIF
ENDDO
DO I = 1, NSQAMPSO
BORNS(1,0)=BORNS(1,0)+BORNS(1,I)
BORNS(2,0)=BORNS(2,0)+BORNS(2,I)
ANS(1,I) = BORNS(1,I) + BORNS(2,I)
ENDDO
DO M = 1, NAMPSO
DO I = 1, NCOLOR
ZTEMP = (0.D0,0.D0)
DO J = 1, NCOLOR
ZTEMP = ZTEMP + CF(J,I)*JAMPH(2,J,M)
ENDDO
DO N = 1, NAMPSO
ANS(2,SQSOINDEXB(M,N))= ANS(2,SQSOINDEXB(M,N)) + ZTEMP
$ *DCONJG(JAMPH(1,I,N))/DENOM(I)
ENDDO
ENDDO
ENDDO
IF (GLU_IJ.NE.0) NHEL(GLU_IJ) = BACK_HEL
END
BLOCK DATA GOODHELS
INTEGER NCOMB
PARAMETER ( NCOMB= 12 )
INTEGER THEL
PARAMETER (THEL=NCOMB*4)
LOGICAL GOODHEL(NCOMB,4)
COMMON /C_GOODHEL/GOODHEL
DATA GOODHEL/THEL*.FALSE./
END
C
C Helper functions to deal with the split orders.
C
INTEGER FUNCTION SQSOINDEXB(AMPORDERA,AMPORDERB)
C
C This functions plays the role of the interference matrix. It can
C be hardcoded or
C made more elegant using hashtables if its execution speed ever
C becomes a relevant
C factor. From two split order indices of the jamps, it return the
C corresponding
C index in the squared order canonical ordering.
C
C CONSTANTS
C
IMPLICIT NONE
INTEGER NAMPSO, NSQAMPSO
PARAMETER (NAMPSO=1, NSQAMPSO=1)
INTEGER NSPLITORDERS
PARAMETER (NSPLITORDERS=2)
C
C ARGUMENTS
C
INTEGER AMPORDERA, AMPORDERB
C
C LOCAL VARIABLES
C
INTEGER I, SQORDERS(NSPLITORDERS)
INTEGER AMPSPLITORDERS(NAMPSO,NSPLITORDERS)
DATA (AMPSPLITORDERS( 1,I),I= 1, 2) / 0, 1/
C
C FUNCTION
C
INTEGER SQSOINDEXB_FROM_ORDERS
C
C BEGIN CODE
C
DO I=1,NSPLITORDERS
SQORDERS(I)=AMPSPLITORDERS(AMPORDERA,I)
$ +AMPSPLITORDERS(AMPORDERB,I)
ENDDO
SQSOINDEXB=SQSOINDEXB_FROM_ORDERS(SQORDERS)
END
INTEGER FUNCTION SQSOINDEXB_FROM_ORDERS(ORDERS)
C
C From a list of values for the split orders, this function
C returns the
C corresponding index in the squared orders canonical ordering.
C
IMPLICIT NONE
INTEGER NSQAMPSO
PARAMETER (NSQAMPSO=1)
INTEGER NSPLITORDERS
PARAMETER (NSPLITORDERS=2)
C
C ARGUMENTS
C
INTEGER ORDERS(NSPLITORDERS)
C
C LOCAL VARIABLES
C
INTEGER I,J
INTEGER SQSPLITORDERS(NSQAMPSO,NSPLITORDERS)
C the values listed below are for QCD, QED
DATA (SQSPLITORDERS( 1,I),I= 1, 2) / 0, 2/
C
C BEGIN CODE
C
DO I=1,NSQAMPSO
DO J=1,NSPLITORDERS
IF (ORDERS(J).NE.SQSPLITORDERS(I,J)) GOTO 1009
ENDDO
SQSOINDEXB_FROM_ORDERS = I
RETURN
1009 CONTINUE
ENDDO
WRITE(*,*) 'ERROR:: Stopping function sqsoindex_from_orders'
WRITE(*,*) 'Could not find squared orders ',(ORDERS(I),I=1
$ ,NSPLITORDERS)
STOP
END
INTEGER FUNCTION GETORDPOWFROMINDEX_B(IORDER, INDX)
C
C Return the power of the IORDER-th order appearing at position
C INDX
C in the split-orders output
C
IMPLICIT NONE
INTEGER NSQAMPSO
PARAMETER (NSQAMPSO=1)
INTEGER NSPLITORDERS
PARAMETER (NSPLITORDERS=2)
C
C ARGUMENTS
C
INTEGER IORDER, INDX
C
C LOCAL VARIABLES
C
INTEGER I
INTEGER SQSPLITORDERS(NSQAMPSO,NSPLITORDERS)
C the values listed below are for QCD, QED
DATA (SQSPLITORDERS( 1,I),I= 1, 2) / 0, 2/
C
C BEGIN CODE
C
IF (IORDER.GT.NSPLITORDERS.OR.IORDER.LT.1) THEN
WRITE(*,*) 'INVALID IORDER B', IORDER
WRITE(*,*) 'SHOULD BE BETWEEN 1 AND ', NSPLITORDERS
STOP
ENDIF
IF (INDX.GT.NSQAMPSO.OR.INDX.LT.1) THEN
WRITE(*,*) 'INVALID INDX B', INDX
WRITE(*,*) 'SHOULD BE BETWEEN 1 AND ', NSQAMPSO
STOP
ENDIF
GETORDPOWFROMINDEX_B=SQSPLITORDERS(INDX, IORDER)
END
SUBROUTINE GET_NSQSO_B(NSQSO)
C
C Simple subroutine returning the number of squared split order
C contributions returned in ANS when calling SMATRIX_SPLITORDERS
C
IMPLICIT NONE
INTEGER NSQAMPSO
PARAMETER (NSQAMPSO=1)
INTEGER NSQSO
NSQSO=NSQAMPSO
END
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