here's a pseudo-code-ish description of how you might approach this: 

my $hash={};
while (have_records){
       my $time = (date_from_record) . "-" . (time_from_record);
       if ( ! defined($hash->{$time} ) {
             $hash->{$time} = {   min => SOME_VERY_LARGE_NUMBER,
                                  max => 0 
                               }
        }

        $hash->{$time}->{min} = ( (VALUE_FROM_RECORD) < $hash->{$time}
+->{min} ? 
                                  (VALUE_FROM_RECORD) : $hash->{$time}
+->{min} ) ;

        $hash->{$time}->{max} = ( (VALUE_FROM_RECORD) > $hash->{$time}
+->{max} ? 
                                  (VALUE_FROM_RECORD) : $hash->{$time}
+->{max} ) ;
}

# NOTE:  change (date_from_record), (have_records and other 
# psuedo-values to things that are reasonable.

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Peter L. Berghold -- Unix Professional
Peter -at- Berghold -dot- Net; AOL IM redcowdawg Yahoo IM: blue_cowdawg

In reply to Re: Parse CSV lines and process for each second by blue_cowdawg
in thread Parse CSV lines and process for each second by capriguy84

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