How to compare two data frame

Question

df1

 index           Count
 Duliajan Area      2
 HAPJAN             2
 KATHALGURI         2

df2

 Location           Category
0        NAGAJAN        0
1        JORAJAN        0
2     KATHALGURI        0
3         HEBEDA        0
4          MAKUM        0
5       BAREKURI        0
6        BAGHJAN        0
7  Duliajan Area        0
8      LANGKASHI        0
9         HAPJAN        0

I need this output:

0        NAGAJAN        0
1        JORAJAN        0
2     KATHALGURI        2
3         HEBEDA        0
4          MAKUM        0
5       BAREKURI        0
6        BAGHJAN        0
7  Duliajan Area        2
8      LANGKASHI        0
9         HAPJAN        2

@Corralien it was covered in the duplicate, `map` should be used here `df2['Location'].map(df1.set_index('index')['Count']).fillna(df2['Count'])` — mozway, Jan 07 '23 at 16:36

score 0 · Answer 1 · answered Jan 07 '23 at 16:07

0

You can use pandas merge function for example:

df2 = df2.rename(columns={"Location": "index"})
result = pd.merge(df1, df2, on="index")

answered Jan 07 '23 at 16:07

tomerar

805
5
10

I'mahdi · Accepted Answer · 2023-01-07T16:47:10.180

0

You can create dict from two columns of df1 then using map on the df2.

d = dict(zip(df1['index'], df1['Count']))
df2['Category'] = df2['Location'].map(d).fillna(df2['Category']).astype(int)
print(df2)

Output:

        Location  Category
0        NAGAJAN         0
1        JORAJAN         0
2     KATHALGURI         2
3         HEBEDA         0
4          MAKUM         0
5       BAREKURI         0
6        BAGHJAN         0
7  Duliajan Area         2
8      LANGKASHI         0
9         HAPJAN         2

edited Jan 07 '23 at 16:47

answered Jan 07 '23 at 16:12

I'mahdi

23,382
5
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How can I get the whole value instead of float. – venkateswaran Jan 07 '23 at 16:18
@venkateswaran, what do you mean whole value? – I'mahdi Jan 07 '23 at 16:44
1

Instead of 2.0, 0.0. I need 0,2 like that – venkateswaran Jan 07 '23 at 16:46

score 0 · Answer 3 · answered Jan 07 '23 at 16:13

Concat your dataframe then drop duplicates:

mapping = {'index': 'Location', 'Count': 'Category'}
out = (pd.concat([df2, df1.rename(columns=mapping)])
         .drop_duplicates('Location', keep='last')
         .reset_index(drop=True))
print(out)

# Output
        Location  Category
0        NAGAJAN         0
1        JORAJAN         0
2         HEBEDA         0
3          MAKUM         0
4       BAREKURI         0
5        BAGHJAN         0
6      LANGKASHI         0
7  Duliajan Area         2
8         HAPJAN         2
9     KATHALGURI         2

How to compare two data frame

3 Answers3