20131201.06372602.mcp APRL 7.1963 BEBP 7.1979 CASY 7.3879 DONT 7.3196 DUBY 6.3729 FOOT 7.1496 GRAW 7.0046 KNYN 6.7313 LEON 7.4596 MICH 7.5579 RAPH 7.0563 RKST 6.6879 SAMH 6.9529 SHRD 6.2829 SPLN 6.1113 20131202.02185602.mcp APRL -2.1870 BEBP -2.3270 CASY -1.0153 DONT -0.1453 DUBY -1.9920 FOOT -2.1903 GRAW -1.5937 KNYN -2.0403 LEON -0.6237 MICH -1.5737 RAPH -1.3287 RKST -2.5337 SAMH -1.9653 SHRD -2.4087 SPLN -2.2053 #### my %station_name = ( DONT => "1", MICH => "2", LEON => "3", RAPH => "4", SPLN => "5", SHRD => "6", CASY => "7", APRL => "8", FOOT => "9", BEBP => "10", RKST => "11", DUBY => "12", SAMH => "13", GRAW => "14", KNYN => "15", KP01 => "16", KP02 => "17", KP03 => "18", KP04 => "19", KP05 => "20", ); #### for ($i = 0; $i < @rat_event; $i++) { chomp($rat_event[$i]); ($station, $delaytime) = (split /\s+/, $rat_event[$i])[0,1]; # create a Hash for the Stations. if ($station = %station_name) { #I don't know what do do here. } close(rat_event); close(RAT_STA); #### 1 time1 time2 ... time_n 2 time1 time2 ... time_n.