Thanks for all the replies folks!!
Here is the current sub I was working on.
I basically pass a size to test against ($feat_size) and return true (1) or false (0) depending on the following...

sub has_smaller {
    my($f,$job,$step,$layer,$feat_size) = @_;
    my $size_1;
    my $size_2;
    my $tmp_size;
    my %seen = ();
    my $feature_list = ();
    my @unique_list = ();
    $f->DO_INFO("-t layer -e $job/$step/$layer -d SYMS_HIST"); # datab
+ase query initializes "$f->{doinfo}"
    $feature_list = $f->{doinfo}{gSYMS_HISTsymbol}; # reference to a l
+ist of strings

    undef %seen;
    @seen{@$feature_list} = ();
    @unique_list = sort keys %seen;
    foreach my $sym ( @unique_list ){       
        if ($sym =~ /^(?!i|ddi)[a-z_]+(\d+(?:\.\d+)?)(?:[a-z](\d+(?:\.
+\d+)?))?/){
            $size_1 = $1;
            $size_2 = $2;
            $tmp_size = $size_1;
            if (defined $size_2){
                $tmp_size = $size_2 if $size_2 < $size_1;
            }
            if ($tmp_size < $feat_size){
                return 1;
            }
        }
    }
    return 0;
}
[download]