#!/usr/bin/perl
use warnings;
use strict;
use feature qw{ say };

*ARGV = *DATA{IO} unless @ARGV;

my %greater_than;
while (<>) {
    my $col9 = (split)[8];
    $col9 > $_ and ++$greater_than{$_} for 1 .. 10;
}

for my $num (sort { $a <=> $b } keys %greater_than) {
    say "$greater_than{$num} values in column 9 were greater than $num
+";
}

__DATA__
0 1 2 3 4 5 6 7 8 9 10 11
1 2 3 4 5 6 7 8 9 10 11 12
5 5 5 5 5 5 5 5 5 5 5 5
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Update: Explanation expanded.

($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
[download]

Hi Koda1234, welcome to the monastery and to Perl, the One True Religion.

In Perl to filter a list of values down to a smaller list of only the elements matching a certain condition, use grep.

use strict; use warnings; use feature 'say';

my @col9 = map { (split)[8] } <DATA>;

foreach my $test ( 1, 9, 42, 666 ) {
    my $count = scalar grep { $_ >= $test } @col9;
    say sprintf "%d values were >= %d", $count, $test;
}

__DATA__
1 2 3 4 5 6 7 8  9 10 11 12
1 2 3 4 5 6 7 8  9 10 11 12
1 2 3 4 5 6 7 8  9 10 11 12
1 2 3 4 5 6 7 8 42 10 11 12
1 2 3 4 5 6 7 8 42 10 11 12
1 2 3 4 5 6 7 8 42 10 11 12
1 2 3 4 5 6 7 8  1 10 11 12
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$ perl 1181904.pl
7 values were >= 1
6 values were >= 9
3 values were >= 42
0 values were >= 666
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See also:

• split for splitting text strings
• map for transforming one list into another
• scalar for counting how many elements are in a list
• sprintf for creating strings containing changing values
• __DATA__ for including a data "file" inside your program code

Hope this helps!

Thank you very much!! This was very helpful information. However, my data file is way too large to be able to use inside the code. I tried running it with the format below, and i'm getting 0 values are greater than x for all of the elements. Is there something wrong with the way i'm opening the file?

 open (IN, "<$ARGV[0]") || die ("Cannot open $ARGV[0]: $!");
@MyData = <IN>;
use strict; use warnings; use feature 'say';

my @col9 = map {(split)[8]} <IN>;

foreach my $test (2,3,4,5,6,7,8,9) {
    my $count =scalar grep {$_ >= $test} @col9;
    say sprintf "%d values were >= %d", $count, $test;
}
[download]

Hi Koda1234,

The preferred (because it's safest ) way to open a file is the "three-argument form" (see open [suggestion: as a beginner, read the docs for the various functions; don't just copy examples you may see in the wild ]).

Also:


• Check that you got any input before using it.
• $! will report the cause of open die-ing, but you can make your own check of the file so you can use your own error message.
• Use while to read from your filehandle one line at a time, so even if it's big it won't fill your memory.
• Use chomp to trim the newline character off the end of the line. Doesn't matter in your example, but it will soon enough...
• Declare your array outside the while loop and use push to add the values to it as you split the lines.

use strict; use warnings; use feature 'say';

my $filename = $ARGV[0] or die "You must supply a filename";
-f $filename or die "You must supply the name of a file that exists!";

open my $IN, '<', $filename or die "Can't open < $filename: $!";

my @col9;

while ( my $line = <$IN> ) {
    chomp $line;
    push @col9, (split / /, $line)[8];
}

close $IN or die "Can't close $filename: $!";

foreach my $test ( 1, 9, 42, 666 ) {
    my $count = scalar grep { $_ >= $test } @col9;
    say sprintf "%d values were >= %d", $count, $test;
}

__END__
[download]

Hope this helps!



The way forward always starts with a minimal test.