0

I have a df with name,marks and negative. I'm trying to do a cumulative sum and subract negative column.

    df

            name        marks       negative    

    0      marcus       20              0          
    1      marcus       30             10  
    2      marcus       0              20                 
    3      paul         10              0          
    4      bruno        50             50           
    5      bruno        20              0          
    6      lucy          0              5          





    Final df

            name        marks       negative    finsum

    0      marcus       20              0          20
    1      marcus       30             10          40           (20+30-10) - (finsum+marks-negative)
    2      marcus       0              20          20       
    3      paul         10              0          10
    4      bruno        50             50           0
    5      bruno        20              0          20
    6      lucy          0              5          -5

I have tried cumsum() for a single row, But how to add and subract with cumsum() or is there any other way?

Improve this question

1 Answer 1

Reset to default
1

Use GroupBy.cumsum:

df1 = df.groupby('name').cumsum()
df['fin'] = df1['marks'].sub(df1['negative'])

print (df)
     name  marks  negative  fin
0  marcus     20         0   20
1  marcus     30        10   40
2  marcus      0        20   20
3    paul     10         0   10
4   bruno     50        50    0
5   bruno     20         0   20
6    lucy      0         5   -5
Improve this answer
Sign up to request clarification or add additional context in comments.

Comments

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.