如何获取列值与另一个列值比较的索引值

Question

I want something like this.

Index    Sentence
0           I
1           want
2           like 
3           this

Keyword     Index
 want        1
 this        3

I tried with df.index("Keyword") but its not giving for all the rows. It will be really helpful if someone solve this.

Answer 1

Use isin with boolean indexing only:

df = df[df['Sentence'].isin(['want', 'this'])]
print (df)
   Index Sentence
1      1     want
3      3     this

EDIT: If need compare by another column:

df = df[df['Sentence'].isin(df['Keyword'])]
#another DataFrame df2
#df = df[df['Sentence'].isin(df2['Keyword'])]

And if need index values:

idx = df.index[df['Sentence'].isin(df['Keyword'])]
#alternative
#idx = df[df['Sentence'].isin(df['Keyword'])].index