Cumulative sum and percentage on column?

Question

I have a DataFrame like this:

df:

 fruit    val1 val2
0 orange    15    3
1 apple     10   13
2 mango     5    5 
         


        

Answer 1

df['cum_sum'] = df['val1'].cumsum()
df['cum_perc'] = 100*df['cum_sum']/df['val1'].sum()

This will add the columns to df. If you want a copy, copy df first and then do these operations on the copy.