4.2.8 SUBROUTINE ZEORD(MODE, STEER) : Event generator ORDers, default JETSET version

Default routine to define and read user steerings for the event generator, JETSET version. Can be used as an example.

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.
    In the example :
      To /LUDAT1/, /LUDAT2/, /PYPARS/, /PYSUBS/ : JETSET and
      PYTHIA steerings.

CALLED BY :

ZXRUIN, RUn Initialisation (see 4.1.6).

CALLED ROUTINE(S):

VZERO

(CERNLIB routine.)

FFKEY

(CERNLIB FFREAD routine.)

SIDE EFFECTS:

none.

AUTHORS:

M. Berggren, UFRJ

CREATION DATE:

05-APR-1995