Python Dask从行中删除

Question

我正在尝试编写一个脚本，使用dask从CSV中删除信息。我有一个从csv创建的dask df，如下所示：

CUSTOMER ORDERS
  hashed_customer      firstname    lastname    email   order_id    status          timestamp
0      eater 1_uuid  1_firstname  1_lastname  1_email    12345    OPTED_IN     2020-05-14 20:45:15
1      eater 2_uuid  2_firstname  2_lastname  2_email    23456    OPTED_IN     2020-05-14 20:29:22
2      eater 3_uuid  3_firstname  3_lastname  3_email    34567    OPTED_IN     2020-05-14 19:31:55

我有另一个csv与散列_客户，我需要从这个文件中删除。因此，如果此文件中的散列客户在客户订单中，我需要从行中删除firstname、lastname和email，同时保留其余内容，如下所示：

CUSTOMER ORDERS
      hashed_customer      firstname    lastname    email   order_id    status          timestamp
    0      eater 1_uuid         NULL        NULL     NULL    12345    OPTED_IN     2020-05-14 20:45:15
    1      eater 2_uuid  2_firstname  2_lastname  2_email    23456    OPTED_IN     2020-05-14 20:29:22
    2      eater 3_uuid  3_firstname  3_lastname  3_email    34567    OPTED_IN     2020-05-14 19:31:55

我当前的脚本如下所示：

print('FIND ORDERS FROM OPT-OUT CUSTOMERS')
cust_opt_out_order = []
for index, row in df_in.iterrows():
    if row.hashed_eater_uuid in cust_opt_out_id:
        cust_opt_out_order.append(row.order_id)

print('REMOVE OPT-OUT FROM OPT-IN FILE')
df_cust_out = df_in[~df_in['hashed_eater_uuid'].isin(cust_opt_out_id)]

但这是删除整行，现在我需要保留该行，只删除该行中的name和email元素。如何使用pandas从行中删除元素

我想得到一个相当于熊猫的dask：

df_cust_out.loc[df_in['hashed_eater_uuid'].isin(cust_opt_out_id),['firstname','lastname', 'email']]=np.nan

Answer 1

我建议查看Dataframe.where或Series.where方法：

https://docs.dask.org/en/latest/dataframe-api.html#dask.dataframe.DataFrame.where