How to format a number 1000 as “1 000”

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

Answer 1

This is old but the fastest and most elegant way I could find to do this is:

def r_delim(s, e)                                                               
  (a = e%1000) > 0 ? r_delim(s, e/1000) : return; s << a                        
end

r_delim([], 1234567).join(',')

I'll try and add benchmarks at some point.