sub approx {
    my ( $num, $dp ) = @_;
    $dp ||= 6;
    if ( $num =~ m/\d*\.(\d*?)(9{$dp,})\d*/ ) {
        my $exp = 10** (length $1 + length $2);
      return int(($num * $exp) +1 )/$exp;

    }
    elsif ( $num =~ m/\d*\.(\d*?)(0{$dp,})\d*/ ) {
        my $exp = 10** (length $1 + length $2);
      return int($num * $exp)/$exp;
    }
    else {
        return $num;
    }
}