基于其他 dataframe 索引在特定级别上重新索引 Multiindex dataframe

Question

I have a Multiindex dataframe [id, currency] as an input. I want it to be filtered by the price dataframe index on the level currency. Any contribution would be appreciated.

balance dataframe:

                balance
id   currency   
1    JPY        2322
     USD        w3r234
     KWN        23423
2    POPO       234234 
     USDC       3w4234
     BTC         54545
     ETH         2323412

price dataframe:

JPY        0.3
KWN        0.5
POPO       0.2 
USDC       0.5
ETH        0.3

Desired output is the scaled balance dataframe:

                balance
id   currency   
1    JPY        2322
     KWN        23423
2    POPO       234234 
     USDC       3w4234
     ETH         2323412

My code:

idx = price.index
balance = balance.reindex(idx, level='currency', fill_value=0).sort_index()

Answer 1

Access the values of the desired level and filter based on the items present in price dataframe:

df = balance[np.in1d(balance.index.get_level_values(1), price.index)]