Hi!

I have been given a perl script to quickly extract rows from large excel files. It digresses from the scope of what I am working on as it is just a method for extracting data, but I would really like to know how it works. I have limited time to get to grips with it on my own.

Could someone please help me understand this script? It extracts a date, a weather station number and then a particular time. 

#!/usr/bin/perl

use strict;
use warnings;
my ($record, $date, $outfile, $station, $sstation, $linecnt, $pcntg, @
+values);

# creating variables for user specification of date and station
print "Processing \"$ARGV[0]\"...\n";
$date = $ARGV[2];
$station = $ARGV[1];
# create output file named after date being investigated
$outfile = $date.".txt";
$outfile =~ s/ /-/;

# counting number of lines 
print "For Date: $date and Station: $station\n\n";
$linecnt = `wc -l < $ARGV[0]`;
open (INFILE, $ARGV[0]);
open (OUTFILE, ">>", $outfile);

while (<INFILE>) {
   $pcntg = int (($. / $linecnt ) * 100) ;
   print "$pcntg %\r";
   chomp();
   $record = $_;
   @values = split (',',$record);
   $sstation = $values[5];
   $sstation =~ s/ //g;
   if ($values[0] eq $date && $sstation eq $station ) {
      print OUTFILE $record."\n";
#      print "xx".$values[5]."xx\n";
      print "Record written to $outfile...\n";
      last;
   }
}

print "\nFinished\n";
close (INFILE);
close (OUTFILE);

[download]

Best wishes

In reply to Completely New To Perl - Need Help Commenting Script by tevoit

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