pandas apply function with multiple condition?

Question

if i want to apply lambda with multiple condition how should I do it?

df.train.age.apply(lambda x:0 (if x>=0 and x<500))

or is there much better methods?

Answer 1

Alternatively, you can use loc:

import pandas as pd

df = pd.DataFrame({"age": [-100, 300, 400, 500, 600, 700]})
df["age"].loc[(df["age"] < 500) & (df["age"] >= 0)] = 0

Now your df looks like this:

    age
0   -100
1   0
2   0
3   500
4   600
5   700

Answer 2

You can use Nested List comprehension within the lambda function.

Or

Write a function and call the function on your series using Lambda

Answer 3

The most straightforward way is simply define a function.

Lambda function is great when the function is simple and straightforward otherwise it would be a pain to read and hence not really a recommended practice.