创建新列，其中来自两个不同数据帧的两列相同

Question

I have two dataframes.

1:

---

   pid  cluster
7993355 0   0
8180238 0   5
8174589 0   7
8168267 0   10
8264548 0   10
8252159 0   0
8388741 0   6
8346358 0   2
8194226 0   8
8187866 0   3
8133728 0   1
8215624 0   6
8124250 0   0
8382996 0   5
8151852 0   0
8130044 0   2
8017035 0   5
8108438 0   0
8245152 0   1
8047538 0   3
8070691 0   7
8344660 0   5
8148647 0   6
8157608 0   10
8352127 0   8

2:

---

pid cluster count
0   0   0   8
1   0   1   2
2   0   2   3
3   0   3   2
4   0   4   1
5   0   5   5
6   0   6   4
7   0   7   3
8   0   8   4
9   0   10  3

My goal is to join these two dataframes when both pid and cluster are the same for example if the pid and cluster are both 0 I would like the next dataframe to have the value 8 for count. I would like to this autonomously. I have tried using a fucntion : train['count'] = np.where(((sample['pid'] == train['pid'])&(sample['cluster']==train['cluster'])), sample['count'], 0) But it doesnt work. Pd.Merge etc will not work as both are of different dimensions I have only provide a small snippet of the dataframes. Any help would be appreciated!!

Answer 1

尝试这个

df2[df2['pid'].isin(pd.unique(df1['pid'])) & df2['count'].isin(pd.unique(df1['count'])) ]