Count the frequency that a value occurs in a dataframe (multiple column)

Question

I want to count the frequency of a value that are same in 2 column, also adding a column at the end that display the counting number & delete the first cloumn.

The dataframe I have

| Column A | Column B | Column C |
| -------- | -------- | -------- |
| Column A | Cat      | Fish     |
| Column A | Cat      | Apple    |
| Column A | Cat      | Apple    |
| Column A | Dog      | Lemon    |
| Column A | Dog      | Fish     |
| Column A | Dog      | Fish     |

The expected outcome is like

| Column A | Column B | Column C | 
| -------- | -------- | -------- | 
| Cat      | Fish     |     1    |
| Cat      | Apple    |     2    |
| Dog      | Lemon    |     1    |
| Dog      | Fish     |     2    |

I have tried the

df['Column B'].value_counts()

But I don't know to handle 2 cloumn at the same time.

Timeless · Accepted Answer · 2022-11-25 16:13:33Z

1

You can use GroupBy.count :

out = (
        df.groupby(["Column B", "Column C"],
                   as_index=False, sort=False)
        ["Column A"].count()
       )

# Output :

print(out)
     Column B    Column C  Column A
0   Cat         Fish              1
1   Cat         Apple             2
2   Dog         Lemon             1
3   Dog         Fish              2

answered Nov 25, 2022 at 16:13

Timeless

38.3k6 gold badges33 silver badges54 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Count the frequency that a value occurs in a dataframe (multiple column)

1 Answer 1

# Output :

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

# Output :

Comments

Your Answer

Sign up or log in

Post as a guest

Related