average-number-of-votes-on-all-sites/report

#!/usr/bin/env perl
use strict;
use warnings;
use Text::CSV;

my @language_sites = qw();

my $csv = Text::CSV->new;
my $top_row = $csv->getline(*STDIN);
my @rows = ();
while (my $row = $csv->getline(*STDIN)) {
    $row->[0] =~ s/^StackExchange\.(.*)/lc($1)/e;
    push @rows, $row;
}

sub report {
    my ($include_top, $include_bottom, $include_median, @sites) = @_;
    print "                    up    down\n";
    for (my $rank = 0; $rank < @rows; $rank++) {
        my @row = @{$rows[$rank]};
        my $site = $row[0];
        printf "%-18s %5.2f %5.2f\n", $site, @row[4,5]
          if $rank < $include_top
          or $include_median && $rank == @rows / 2
          or $rank >= @rows - $include_bottom
          or grep {$_ eq $site} @sites;
    }
}

if (@ARGV == 0) {
    report(scalar(@rows), 0, ());
} elsif ($ARGV[0] eq '--help') {
    print <<EOF;
Usage: $0 [STYLE]
Show the average number of upvotes and downvotes per post on Stack Exchange
sites. Deleted posts are excluded.

This script reads CSV data on standard input. The data can be retrieved from
http://data.stackexchange.com/stackoverflow/query/195762/average-number-of-votes-on-all-sites
EOF
} elsif ($ARGV[0] eq 'cs') {
    report(6, 1, 1, qw(astronomy biology chemistry cogsci crypto cs cstheory
                       earthscience linguistics
                       math matheducators mathoverflow
                       philosphy physics programmers
                       scicomp stackoverflow stats tex));
} elsif ($ARGV[0] eq 'it') {
    report(1, 1, 1, qw(android apple arduino blender codegolf codereview
                       dba drupal dsp ebooks electronics expressionengine
                       gamedev gis joomla magento mathematica
                       networkengineering programmers
                       raspberrypi reverseengineering salesforce
                       security serverfault sharepoint stackoverflow superuser
                       tex tor tridion ubuntu unix ux
                       webapps webmasters windowsphone wordpress));
} elsif ($ARGV[0] eq 'lang') {
    report(1, 1, 1, qw(chinese ell english french german italian
                       japanese linguistics russian spanish writers));
} elsif ($ARGV[0] =~ /[[:space:[,]/) {
    report(0, 0, 0, split(/[[:space:],]+/, $ARGV[0]));
} else {
    die "Unknown report style";
}