I used this script, an example from the docs, to test memory use. 5m is way too much. Cut it back to 2m, and you're ready to roll:
#!/usr/bin/perl

use strict;
use warnings;
use Statistics::Descriptive::Weighted;

my @data = (1..2000000);
my $stat = Statistics::Descriptive::Full->new(); 
$stat->add_data(@data); 
print $stat->quantile(1), "\n";

[download]
Update: Maybe this might help:
#!/usr/local/bin/perl

use strict;
use warnings;

my @numbers = (1..2000000);
printf "Percentile %d%% at %f\n", $_, percentile($_,\@numbers)
for qw/25 75/;

sub percentile {
    my ($p,$aref) = @_;
    my $percentile = int($p * $#{$aref}/100);
    return (sort @$aref)[$percentile];
}

[download]

In reply to Re: Using Statistics::Descriptive for percentiles by Khen1950fx
in thread Using Statistics::Descriptive for percentiles by Hena

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