Python実践データ分析100本ノック第2版でエラー

ノック25:利用履歴データを集計しよう

でつまづき30分かかったので共有します。

uselog_customer = uselog_months.groupby("customer_id").agg(["mean", "median", "max", "min"])["count"]
uselog_customer = uselog_customer.reset_index(drop=False)
uselog_customer.head()

エラー内容

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
/usr/local/lib/python3.10/dist-packages/pandas/core/groupby/groupby.py in _agg_py_fallback(self, how, values, ndim, alt)
   1873         try:
-> 1874             res_values = self.grouper.agg_series(ser, alt, preserve_dtype=True)
   1875         except Exception as err:

24 frames
TypeError: Could not convert string '201804201805201806201807201808201809201810201811201812201901201902201903' to numeric

The above exception was the direct cause of the following exception:

TypeError                                 Traceback (most recent call last)
/usr/local/lib/python3.10/dist-packages/pandas/core/groupby/groupby.py in _agg_py_fallback(self, how, values, ndim, alt)
   1876             msg = f"agg function failed [how->{how},dtype->{ser.dtype}]"
   1877             # preserve the kind of exception that raised
-> 1878             raise type(err)(msg) from err
   1879 
   1880         if ser.dtype == object:

TypeError: agg function failed [how->mean,dtype->object]

["count"]の位置を手前に持ってくることでエラー回避できた。

uselog_customer = uselog_months.groupby("customer_id")["count"].agg(["mean", "median", "max", "min"])
uselog_customer = uselog_customer.reset_index(drop=False)
uselog_customer.head()