4.2.9 SUBROUTINE ZEORD(MODE, STEER) : Event generator ORDers, PYTHIA version

Routine to define and read user steerings for the event generator, PYTHIA version. If MODE = 0, then the routine defines keys for FFREAD, if it is $\neq$ 0 then the routine reacts on the values read be FFREAD. So, the calling routine must do something like

          CALL ZEORD(0,STEER)
                .
                .
            (other key definitions)
                .
                .
                .
          CALL FFGO
          CALL ZEORD(1,STEER)
                .

This is what ZXRUIN does. Note that the variables read in by FFREAD must be in a common, even if SGV uses them only in this routine !

ARGUMENTS:

INPUT :

    MODE : 0 -> routine should define key-words, and
                default values.
           <> 0 -> load values of keys read from the steering file
                to the right common-blocks, do initialisation etc.

OUTPUT :

    STEER : Steering info. The event generator uses row 2:
                  STEER(2,0)   : Type of event to be generated.
                         ,1)   : CMS energy of reaction to be simulated.
                         ,2)   : Lifetime of B hadrons.
                         ,4)   : 0.0 -> use fixed primary vertex position.
                                 1,0 -> generate primary vertex position.
                                        event by event.
                         ,5-7) : Average production point.
                         ,8-10): Spread in production-point.
             In addition STEER(1,0) is an error flag:
                     0 : no error
                     1 : error, but go on
                     -2 : error, stop this run
                 All other position of the row are free to use.

IMPLICIT INPUTS:

    From /ESIVAR/ : local variables used for clarity

IMPLICIT OUTPUTS:

    To /ESIVAR/ : local variables used for clarity, after their values
      have been set by FFREAD.
    To /LUDAT1/, /LUDAT2/, /LUDAT3/, /PYPARS/, /PYSUBS/ : JETSET and
      PYTHIA steerings, pre-PYTHIA6. Or:
    To /PYDAT1/, /PYDAT2/, /PYDAT3/, /PYPARS/, /PYSUBS/ : PYTHIA6
      steerings.

CALLED BY :

ZXRUIN, RUn Initialisation (see 4.1.6).

CALLED ROUTINE(S):

ZUCODS (see 4.7.15)

(To COpy Double prec to Single prec)

ZUCOSD (see 4.7.16)

(To COpy Single prec to Double prec)

PYINIT

(PYTHIA routine.)

VZERO,LENOCC,CLEFT,CLTOU

(CERNLIB routines.)

FFKEY,FFGO

(CERNLIB FFREAD routines.)

SIDE EFFECTS:

none.

AUTHORS:

M. Berggren, IPNL

CREATION DATE:

20-JAN-1998