4.1.5 Reading generated events from an external file

To read the LUJETS common-block from an external file, add the card

+USE,EXTREAD.

into the cradle, and add the card LUJETS_UNIT into the steering file. The value of the card is clearly the logical unit number of the file to read the events form. Make sure that the file is indeed assigned/soft-linked to the unit.

The LUJETS common-block should previously have been writen by the event-generator program by the write statement

          WRITE (LUNIT)
     +      N,((K(I,J),J=1,5),(P(I,J),J=1,5),(V(I,J),J=1,5),I=1,N)

to be executed once per generated event.

Note that this method will, just as using ntuples, compromise the real-time performance of SGV, since it implies large amounts of I/O. In addition, doing a large scale simulation in this mode will demand large amounts of disk-space: A single track in LUJETS uses 45 Bytes, so a single typical hadronic event with around 200 entries in LUJETS takes 10 kB.

Hence, the method of integrating the generator into SGV (see chapter 4.1.7 ) should be preferred whenever possible.