Dear all,
I have this dataframe:
datatime,T,RH,PSFC,DIR,VEL10,PREC,RAD,CC,FOG
2012-01-01 06:00, 0.4,100, 911,321, 2.5, 0.0, 0, 0,0
2012-01-01 07:00, 0.8,100, 911,198, 0.8, 0.0, 0, 22,0
2012-01-01 08:00, 0.6,100, 912, 44, 1.2, 0.0, 30, 22,0
2012-01-01 09:00, 3.1, 76, 912, 22, 0.8, 0.0, 134, 44,0
2012-01-01 10:00, 3.4, 77, 912, 37, 0.5, 0.0, 191, 67,0
2012-01-01 11:00, 3.5,100, 912,349, 0.4, 0.0, 277, 44,0
2012-01-01 12:00, 3.6,100, 912, 17, 0.9, 0.0, 292, 22,0
2012-01-01 13:00, 3.5,100, 912, 28, 0.3, 0.0, 219, 44,0
2012-01-01 14:00, 3.3, 68, 912, 42, 0.5, 0.0, 151, 22,0
....
....
I would like to plot and analyse different part of it. Consequently I have
created the following variables in order to manage different period:
start_date = np.array(['2012-01-01 06:00','2013-01-01 06:00','2014-01-01
06:00'])
end_date = np.array(['2013-01-01 05:00','2014-01-01 05:00','2015-01-01
05:00'])
However, if I try to perform the following cycle:
for ii in range(0, 1):
pd.read_csv('dati.csv',delimiter=',',header=0,parse_dates=True,
na_values=-999)
df['datatime'] = df['datatime'].map(lambda x: datetime.strptime(str(x),
"%Y-%m-%d %H:%M"))
#
mask = (df['datatime'] > start_date[ii]) & (df['datatime'] <= end_date[ii])
I get the following error:
return _get_dtype_type(np.dtype(arr_or_dtype))
File "/usr/lib/python2.7/dist-packages/numpy/core/_internal.py", line 173, in
_commastring
(len(result)+1, astr))
ValueError: format number 1 of "2012-01-01 06:00" is not recognized
On the contrary, if I use the simple variables:
start_date = 2012-01-01 06:00
end_date = 2013-01-01 05:00
without the cycle, it works.
I really do not understand why.
Thanks a lot,
Diego
--
https://mail.python.org/mailman/listinfo/python-list
