在python中进行迭代时如何处理datetime的NaT值？

Question

I am using below code to convert datetime values to integers. It works great except for NaT values. If I am doing this in an iteration, how can I handle NaT values so that I don't get errors such as 'NaTType does not support timetuple'?

import time
from datetime import datetime
t=datetime.now()
t1=t.timetuple()
int(time.mktime(t1)/60/60/24)

Here is the code to create sample data and what I have tried to iterate so far:

create data:

df = pd.DataFrame(data={'date':['05/16/16',''], 'Indicator':[1,0]})
df['date']=pd.to_datetime(df['date'])

Data:

   Indicator       date
0          1 2016-05-16
1          0        NaT

Iteration code:

def date2int(df):
    if df.date:
        t=df['date']
        t1=t.timetuple()
        return int(time.mktime(t1))
df['date2int']=df.apply(date2int,axis=1)

Error message:

Traceback (most recent call last):

File "", line 1, in df['date2int']=df.apply(date2int,axis=1)

File "/Users/Chen/anaconda/lib/python2.7/site-packages/pandas/core/frame.py", line 4042, in apply return self._apply_standard(f, axis, reduce=reduce)

File "/Users/Chen/anaconda/lib/python2.7/site-packages/pandas/core/frame.py", line 4138, in _apply_standard results[i] = func(v)

File "", line 4, in date2int t1=t.timetuple()

File "pandas/tslib.pyx", line 723, in pandas.tslib._make_error_func.f (pandas/tslib.c:16109)

ValueError: ('NaTType does not support timetuple', u'occurred at index 1')

Answer 1

Solution #1:

def date2int(df):
    if df.date:
        t=df['date']
        try:
            t1=t.timetuple()
            return int(time.mktime(t1))
        except ValueError:
            return None
df['date2int']=df.apply(date2int,axis=1)

Solution #2:

df=df.dropna()