python - ValueError：未转换的数据仍然存在

Question

这是我的功能：

def get_month(date_string, kind = 'month'):
    if kind == 'month':
        date = datetime.datetime.strptime(date_string, '%Y-%m')
    elif kind == 'day':
        date = datetime.datetime.strptime(date_string, '%Y-%m-%d')
    return date.strftime("%B")

我在这里调用了我的函数：

data['purchase_month'] = data['purchase_date'].apply(lambda x: get_month(x, kind = 'day'))
data['first_active_month2'] = data['first_active_month'].apply(lambda x:get_month(x))
data['first_active_year'] = data['first_active_month'].str[:4]

我调用函数来获取一个月的第二行给了我这个错误：已编辑

 Traceback (most recent call last)
<ipython-input-79-bb17fedd582e> in <module>()
 20 
 21 data['purchase_month'] = data['purchase_date'].apply(lambda x:get_month(x, kind = 'day'))
---> 22 data['first_active_month2'] =data['first_active_month'].apply(lambda x: get_month(x))
 23 data['first_active_year'] = data['first_active_month'].str[:4]
 24 

/opt/conda/lib/python3.6/site-packages/pandas/core/series.py in apply(self, func, convert_dtype, args, **kwds)
   3192             else:
   3193                 values = self.astype(object).values
-> 3194                 mapped = lib.map_infer(values, f,convert=convert_dtype)
   3195 
   3196         if len(mapped) and isinstance(mapped[0], Series):

pandas/_libs/src/inference.pyx in pandas._libs.lib.map_infer()

<ipython-input-79-bb17fedd582e> in <lambda>(x)
 20 
 21 data['purchase_month'] = data['purchase_date'].apply(lambda x:get_month(x, kind = 'day'))
---> 22 data['first_active_month2'] =data['first_active_month'].apply(lambda x: get_month(x))
     23 data['first_active_year'] = data['first_active_month'].str[:4]
     24 

<ipython-input-79-bb17fedd582e> in get_month(date_string, kind)
 14 def get_month(date_string, kind = 'month'):
 15     if kind == 'month':
---> 16         date = datetime.datetime.strptime(date_string, '%Y-%m')
     17     elif kind == 'day':
     18         date = datetime.datetime.strptime(date_string, '%Y-%m-%d')

/opt/conda/lib/python3.6/_strptime.py in _strptime_datetime(cls, data_string, format)
    563     """Return a class cls instance based on the input string and the
    564     format string."""
--> 565     tt, fraction = _strptime(data_string, format)
    566     tzname, gmtoff = tt[-2:]
    567     args = tt[:6] + (fraction,)

/opt/conda/lib/python3.6/_strptime.py in _strptime(data_string, format)
    363     if len(data_string) != found.end():
    364         raise ValueError("unconverted data remains: %s" %
--> 365                           data_string[found.end():])
    366 
    367     iso_year = year = None

ValueError: unconverted data remains: -01

我不知道我在这方面做错了什么。我尝试了在 Stackoverflow 上找到的不同解决方案，但似乎都没有。

标签： pythonpython-3.xdatetime