Example: Loop over all MC generated positrons

              ITK = KPDIR ('E+', KMONTE)
         10   IF (ITK .EQ. 0)  GO TO 90
        C     ... e+ analysis ...
              ITK = KFOLLO (ITK)
              GO TO 10
         90   CONTINUE ...

KPDIR ('particle-name', ICLASS)

'particle-name': Character string (1 to 12 characters). ICLASS: Track class (see 7.4.1): KRECO or KMONTE or a track number ITKRST if ITKRST has been used before to define the rest frame for a Lorentz boost (see 9.6).

KFOLLO (ITK)

The following particle with the same particle name in the same class.

Remarks:

The term ``FOLLOwing'' refers to some arbitrary ordering. Lower case characters in particle names are translated to upper case. It is safest, however, to use only upper case characters with ALPHA.