1.查数据的类型
dataframe.dtype()

2.修改数据类型
df['launched']=pd.to_datetime(df.launched) df['deadline ']=pd.to_datetime(df.deadline)
然后再次打印他们的类型,我们就会发现他们类型的变化;

3.删除时分秒
在type为object的状态下转化将 2015-04-07 08:35:00 转化为2015-04-07
#cut the datetime
df['launched'] = df.launched.str.slice(0, 11)
print(df['launched'].head())
print()
# change the type of column[launched] into datetime;
df['launched']=pd.to_datetime(df.launched, dayfirst=True)
print(df['launched'].head())
print('----------------------------------------------------------------')
print()
df['deadline']=pd.to_datetime(df.deadline, dayfirst=True)
print(df['deadline'].head())
