Question: I need a way to format numbers. I stored some numbers in my DB table, e.g. `12500`, and would like to print them in this format `12 500` (so there is a space every 3 digits). Is there an elegant way to do this?

Answer: 
see: <http://www.justskins.com/forums/format-number-with-comma-37369.html>

there is no built in way to it ( unless you using Rails, ActiveSupport Does have methods to do this) but you can use a Regex like 

```
formatted_n = n.to_s.reverse.gsub(/...(?=.)/,'\&,').reverse

```
Activesupport uses this regexp (and no reverse reverse).

```
10000000.to_s.gsub(/(\d)(?=(\d\d\d)+(?!\d))/, "\\1 ") #=> "10 000 000"

```