Cumulative sum and percentage on column?
PythonPandasDataframeCumulative SumPython Problem Overview
I have a DataFrame like this:
df:
fruit val1 val2
0 orange 15 3
1 apple 10 13
2 mango 5 5
How do I get Pandas to give me a cumulative sum and percentage column on only val1?
Desired output:
df_with_cumsum:
fruit val1 val2 cum_sum cum_perc
0 orange 15 3 15 50.00
1 apple 10 13 25 83.33
2 mango 5 5 30 100.00
I tried df.cumsum(), but it's giving me this error:
> TypeError: ufunc 'isnan' not supported for the input types, and the inputs could not be safely coerced to any supported types according to the casting rule ''safe''
Python Solutions
Solution 1 - Python
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.
Solution 2 - Python
It's a good answer, but written in 2014. I just modified a little bit, so it can pass the compiler and results looks similar to the example.
df['cum_sum'] = df["val1"].cumsum()
df['cum_perc'] = round(100*df.cum_sum/df["val1"].sum(),2)