Pandas: sum up multiple columns into one column without last column
If I have a data frame similar to this one
Apples Bananas Grapes Kiwis
2 3 nan 1
1 3 7 nan
nan nan 2 3
I would like to add a column like this
Apples Bananas Grapes Kiwis Fruit Total
2 3 nan 1 6
1 3 7 nan 11
nan nan 2 3 5
I guess you could use df['Apples'] + df['Bananas'] and so on, but my actual dataframe is much larger than this. I was hoping a formula like df['Fruit Total']=df[-4:-1].sum could do the trick in one line of code. That didn't work, however. Is there any way to do it without explicitly summing up all columns? How pandas sum multiple columns ?
For pandas sum multiple columns, you can perform this by first selecting it by iloc and then apply sum:
df['Fruit Total']= df.iloc[:, -4:-1].sum(axis=1)
print (df)
Apples Bananas Grapes Kiwis Fruit Total
0 2.0 3.0 NaN 1.0 5.0
1 1.0 3.0 7.0 NaN 11.0
2 NaN NaN 2.0 3.0 2.0
And getting the total of all columns, you can use:
df['Fruit Total']= df.sum(axis=1)