如何使用DataFrame连接两列和标签类别？

Question

我有两个很大的列，我想连接在一起，然后为标签赋值

ed_adm_order_md_dept    adm_order
INTERNAL MEDICINE       NaN
INTERNAL MEDICINE       NaN
INTERNAL MEDICINE       NaN
     NaN                ADMIT FOR SURGERY
EMERGENCY MEDICINE      NaN
INTERNAL MEDICINE       NaN
INTERNAL MEDICINE       NaN
INTERNAL MEDICINE       NaN
ORTHOPEDIC SURGERY      NaN
                        ADMIT
                        ADMIT
                        ADMIT

输出可能是这样的

ed_adm_order_md_dept    
INTERNAL MEDICINE       
INTERNAL MEDICINE       
INTERNAL MEDICINE      
***ADMIT FOR SURGERY***                
EMERGENCY MEDICINE      
INTERNAL MEDICINE       
INTERNAL MEDICINE       
INTERNAL MEDICINE       
ORTHOPEDIC SURGERY      
    ADMIT       
ADMIT       
ADMIT

Answer 1

我想你想要这样的东西：

df.ed_adm_order_md_dept.where(df.ed_adm_order_md_dept, df.adm_order)

即，取第一列所在的值，否则取第二列。