Using sprintf:

use strict;
use warnings;

my @num = qw[ 1.3e-3 3.7e-5 102 46 1e-4 1e-12 ];

my @a;
my $base;

for (sort {$b <=> $a} @num) {
    my ($i) = sprintf('%e', $_) =~ /([-+]\d+)/;
    $base //= $i;
    $a[$base - $i] = $_;
}

say $_ // 0 for @a;
[download]

Results:

102
46
0
0
0
1.3e-3
1e-4
3.7e-5
0
0
0
0
0
0
1e-12
[download]