perl数字格式转换

查看mytop源码，学到的几个小技巧，获益匪浅

 

#!/usr/bin/perl
use strict;
use warnings;
use Data::Dumper;

my $number = $ARGV[0];
my $c = $ARGV[1];

sub commify($)
{
    local $_  = shift;
    chomp($_);
    return 0 unless defined $_;
    1 while s/^(\d+)(\d{3})/$1,$2/ and print Dumper($_);   ##，从右边开始，3位一个
    return $_;
}


sub make_short($)
{
    my $number = shift;
    my $n = 0;
    while ($number > 1_025) { $number /= 1024; $n++; };
    return sprintf "%.1f%s", $number, ('','k','M','G', 'T')[$n];  ##切片
}


print commify($number),"\n";
print make_short($number),"\n" if $c;

# perl commify.pl 1230098 y

$VAR1 = '1230,098';
$VAR1 = '1,230,098';
1,230,098
1.2M

[root@cz perl]# perl commify.pl 1230098
$VAR1 = '1230,098';
$VAR1 = '1,230,098';
1,230,098

 

fyi : http://jeremy.zawodny.com/mysql/mytop/