1 #include "isajet/pilot.h"
2 SUBROUTINE IFRAMS(N1,N2,IFR,PAIR)
3 C----------------------------------------------------------------------
5 C- Purpose and Methods :
6 C- Initialize a center of mass frame for partons N1 to N2
7 C- partons must be consecutive unless PAIR is true
12 C- IFR = index of frame
13 C- PAIR= if false N1, N2 denote a range
14 C- if true N1 and N2 form a pair
16 C- Created 14-AUG-1991 Serban D. Protopopescu
18 C----------------------------------------------------------------------
19 #if defined(CERNLIB_IMPNONE)
22 #include "isajet/pjets.inc"
23 #include "isajet/jetset.inc"
24 #include "isajet/jwork.inc"
25 #include "isajet/frame.inc"
26 INTEGER I,J,K,JADD,N1,N2,IFR
27 DOUBLE PRECISION DPASS(5),DSUM(5)
29 C----------------------------------------------------------------------
31 IF ( N2-N1.EQ.1.OR.PAIR ) THEN
41 C Need double precision boosts
42 CALL DBLVEC(PJSET(1,N1),DSUM)
44 CALL DBLVEC(PJSET(1,I),DPASS)
46 210 DSUM(K)=DSUM(K)+DPASS(K)
47 DSUM(5)=DSQRT(DSUM(4)**2-DSUM(1)**2-DSUM(2)**2-DSUM(3)**2)
53 C Set up and generate final state QCD parton shower.
54 C Boost PJSET with -FRAME.
57 CALL DBOOST(-1,FRAME(1,IFR),PJSET(1,J))