#!/usr/bin/perl -w
use strict;


open(FH,"$ARGV[0]") or die;
my @temp=<FH>;
close FH;
my $mean = Mean(\@temp);
my $var = variance(\@temp);
print "$var\n";
sub estimate_variance {
my ($arrayref) = @_;
my ($mean,$result) = (mean($arrayref),0);
foreach (@$arrayref) { $result += ($_ - $mean)**2 }
return $result / $#{$arrayref};
}
error shown:
Undefined subroutine &main::variance called at variance_try1.pl line 9.

wht can be possible solution??