I got a question about formating decimal number in Python by adding comma in appropriate positions. The most recommend approach is to use built-in locale support. In my opinion, this is not too difficult to implement and there are many approaches. I just want to give an example here as a guideline.

#!/usr/bin/env python
 
def comma(d):
    s = '%0.2f' % d
    a,b = s.split('.')
    l = []
    while len(a) > 3:
        l.insert(0,a[-3:])
        a = a[0:-3]
    if a:
        l.insert(0,a)
    return ','.join(l)+'.'+b
 
if __name__ == '__main__':
    print comma(1123456.12)

Tags: codenone, python, decimal