The purpose of pkfilter is
to reduce the number of "duplicate" picks from a given "station". For
pkfilter, all components which have
matching station code and network code are considered to be the from
the same "station". The rules for what are considered "duplicate" picks
can be found in the specifications file used to design this program:
Pkfilter is location-code friendly and will handle both the TYPE*2K and TYPE*SCNL versions picks and codas.
This module was written by Lynn Dietz for the CISN.