#!/usr/bin/perl --
use strict; use warnings;
use Data::Dump qw/ dd /;
Main( @ARGV );
exit( 0 );
sub Main {
    my $frobnications = ...; # formerly \@full_data ... or DemoFrobnications();
    my( $DE, $FG ) = romulate_DE_FG( $frobnications );
    dd( $DE );
    dd( $FG );
    my( $avgDE, $stddevDE ) = pancakes( $DE );
##    AddColumn( $target, $column );
    AddColumn( $frobnications, ... );
}

sub romulate_DE_FG {
    my( $frobnications ) = @_;
    my( @DE, @FG );
    for my $row ( @$frobnications ){
        ...
        push @DE, ...
    }
    return \@DE, \@FG;
}

sub AddColumn {
    my( $frobnications, $column ) = @_;
    ...
}
sub DemoFrobnications {
    return ...; ## output of dd( \@full_data );
}