根据两列的函数在 Pandas 数据框中选择列值最大的行

Question

I have the following dataframe.

data = {'Name': ["Babu", "Shyam", "Raju", "Anuradha", "Kabira"],
       'Age': [60, 35, 32, 31, 37],
       'Income': [20000, 10000, 8000, 12000, 5000],
       'Stupidity Level': [80, 40, 60, 20, 70],
       'Expenses': [15000,8000,7000,9000,4000]
       }

index = ["Paresh Rawal", "Suniel Shetty", "Akshay Kumar","Tabu", "Gulshan Grover"]

df = pd.DataFrame(data, index)

I am trying to find out a row (person) who saves maximum amount every month.

savings = df["Income"] - df["Expenses"]
savings.max()
5000

In this case, it should return the first row whose savings is maximum (5000). But I am trying to this without actually creating a new column for savings. So want to do something like

df[savings.max()] # should return the row with maximum savings. 
df[(df["Income"] - df["Expenses"]).max()]

But of course, none of this isn't working. Not sure of the correct synatax.

Answer 1

Use idxmax :

df.loc[df["Income"].sub(df["Expenses"]).idxmax()]

output:

Name                Babu
Age                   60
Income             20000
Stupidity Level       80
Expenses           15000
Name: Paresh Rawal, dtype: object

all max

s = df["Income"].sub(df["Expenses"])

out = df[s.eq(s.max())]