Routine to define and read user steerings for the event generator, single particle version. If MODE = 0, then the routine defines keys for FFREAD, if it is 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 !
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.
STEER : Steering info. The event generator uses row 2: STEER(2,0) : JETSET code of particle ,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. ,11-12) : Range in P ,13-14) : Range in theta ,15-16) : Range in phii 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.
From /ESIVAR/ : local variables used for clarity
To /ESIVAR/ : local variables used for clarity, after their values have been set by FFREAD.