h1. range.pl

code=yes

#!/usr/bin/perl -wT

my $num_args = $#ARGV + 1;
if ($num_args != 3) {
    print "\nUsage: range.pl filename startcol endcol\n";
    exit;
}

die "Startcol must be greater than 0." if ( $ARGV[1] < 1 );

my $data_file = $ARGV[0];
my $start_col = $ARGV[1] - 1; # first col in data file for substr cmd starts at 0
my $field_width = $ARGV[2] - $start_col;

my %code_counts;

open(my $fh, "<", $data_file) or die "Cannot open $data_file for read: $!";
while ( <$fh> ) {
    chomp;
    my $code_value = substr $_, $start_col, $field_width;

    if ( exists($code_counts{$code_value}) ) {
        $code_counts{$code_value}++;
    } else {
        $code_counts{$code_value} = 1;
    }
}
close($fh) or warn "Close failed: $!";

print "\nStart = $ARGV[1] End = $ARGV[2]\n";
print "Code : Count\n";
print "---- : -----\n";

foreach my $code_number ( sort keys %code_counts ) {
    my $result = sprintf("%4s : %4s\n", $code_number, $code_counts{$code_number});
    print $result;
}