negative numbers and integer division

[Rainer Deyke]

Matthew Wilson wrote:
> I thought that -1 // 12 would be 0 also.  I'm writing a simple monthly
> date class and i need (-1,2001) to be translated to (11,2000).  Any
> ideas?

Luckily for you, Python integer division does the right thing.  You
*want* -1 // 12 to be -1 for your application.

def normalize_date(month, year):
  return (month % 12, year + month // 12)

normalize_date(-1, 2001) # Returns (11, 2000)


'normalize_date' as given assumes 'month' is in the range from 0 to 11; use
this if your months are in the range from 1 to 12:

def normalize_date(month, year):
  return ((month - 1) % 12 + 1, year + (month - 1) // 12)



-- 
Rainer Deyke - rainerd at eldwood.com - http://eldwood.com