python 3.6
pandas 0.23.3
has a DataFrame, as follows:
import pandas as pd
arr = [[10,10,1],[22,24.2,1.1],[15,15,1],[9,8.1,0.9],[50,55,1.1]]
df = pd.DataFrame(arr,columns=["volume","amount","price"]) volume amount price
0 10 10.0 1.0
1 22 24.2 1.1
2 15 15.0 1.0
3 9 8.1 0.9
4 50 55.0 1.1requires the sum of each row of the volume column to get the total column
volume amount price total
0 10 10.0 1.0 10.0
1 22 24.2 1.1 32.0
2 15 15.0 1.0 47.0
3 9 8.1 0.9 56.0
4 50 55.0 1.1 106.0my current way of writing:
for index in df.index:
num = df[df.index < index]["volume"].sum()
df.loc["total"] = num