Question

$ cat .t.py 
import re
from datetime import datetime as dtt

oldestDate = dateComp = dtt.strptime('1.1.1001', '%d.%m.%Y')
dateComp = dtt.strptime('11.1.2011', '%d.%m.%Y')
ind = re.sub(" days,.*", "", str((dateComp - oldestDate)))

print ind
print dateComp - oldestDate
$ python .t.py 
368905
368905 days, 0:00:00

How can I get days only without the regex code-smell? The problem escalate because I need to use the index in many locations. So some cleaner way to do this?

Answer 1

Don’t use str() so soon. The result you get back from subtracting one datetime from another is a timedelta object, which has a .days property that you can read.

(dateComp - oldestDate).days

Note that reading only the .days property will mean that it will round down the difference – if you instead want to round to the nearest number of days, you’ll need to add some logic to check the .seconds property to see whether it’s closer to 0 or 86400.