How do I create a new pandas dataframe column with the contents of another, but only if the other column meets a condition?

Question

I have this line of code:

df['new_column']=df['price'][df['bathrooms']>=2 and df['bathrooms']<3]

Basically, I want to create a new column with the price of a listing (from column price), but only if the bathrooms column contains a value greater than or equal to 2, but less than three. I'm getting the error

The truth value of a Series is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all().

How do I correct this code?

Thank you!

Answer 1

You need proper parathensis, you cannot use 'and' use ampsand (&) instead and use loc instead, try:

df['new_column']=df.loc[(df['bathrooms']>=2) & (df['bathrooms']<3), 'price']

Answer 2

you can use this: query in pandas

df1 =df.query('bathrooms>=2 and bathrooms<3')
df1[['price']]