pandas_datetime_error.py

from datetime import datetime, timedelta
from pandas import *

s  = Series(date_range('2012-1-1', periods=3, freq='D'))
s
# Out[52]: 
# 0   2012-01-01 00:00:00
# 1   2012-01-02 00:00:00
# 2   2012-01-03 00:00:00

td = Series([ timedelta(days=i) for i in range(3) ])
td
# Out[53]: 
# 0            0:00:00
# 1     1 day, 0:00:00
# 2    2 days, 0:00:00

df = DataFrame(dict(A = s, B = td))
df
# Out[54]: 
#                     A                B
# 0 2012-01-01 00:00:00          0:00:00
# 1 2012-01-02 00:00:00   1 day, 0:00:00
# 2 2012-01-03 00:00:00  2 days, 0:00:00

df['C'] = df['A'] + df['B']
# ---------------------------------------------------------------------------
# TypeError                                 Traceback (most recent call last)
# <ipython-input-65-7057e174d79e> in <module>()
# ----> 1 df['C'] = df['A'] + df['B']

# /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pandas/core/series.pyc in wrapper(self, other)
#      91             if self.index.equals(other.index):
#      92                 name = _maybe_match_name(self, other)
# ---> 93                 return Series(wrap_results(na_op(lvalues, rvalues)),
#      94                               index=self.index, name=name)
#      95 

# /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pandas/core/series.pyc in na_op(x, y)
#      63             if isinstance(y, np.ndarray):
#      64                 mask = notnull(x) & notnull(y)
# ---> 65                 result[mask] = op(x[mask], y[mask])
#      66             else:
#      67                 mask = notnull(x)

# TypeError: ufunc add cannot use operands with types dtype('<M8[ns]') and dtype('O')

s - s.max()
# ---------------------------------------------------------------------------
# AttributeError                            Traceback (most recent call last)
# <ipython-input-66-8d53e24db927> in <module>()
# ----> 1 s - s.max()

# /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pandas/core/series.pyc in wrapper(self, other)
#      78 
#      79         if (com.is_datetime64_dtype(self) and
# ---> 80             com.is_datetime64_dtype(other)):
#      81             lvalues = lvalues.view('i8')
#      82             rvalues = rvalues.view('i8')

# /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pandas/core/common.pyc in is_datetime64_dtype(arr_or_dtype)
#    1003         tipo = arr_or_dtype.type
#    1004     else:
# -> 1005         tipo = arr_or_dtype.dtype.type
#    1006     return issubclass(tipo, np.datetime64)
#    1007 

# AttributeError: 'Timestamp' object has no attribute 'dtype'