merge() fehlt 1 erforderliche Positions Argument: 'right'

Question

ich ein Tutorial tue und ich habe ein Problem: Mein Code:

import html5lib 
import quandl 
import pandas as pd 
import pickle 

pd.read_html("https://simple.wikipedia.org/wiki/List_of_U.S._states") 
main_df = pd.DataFrame() 
fiddy_states = pd.read_html('https://simple.wikipedia.org/wiki/List_of_U.S._states') 
for abbv in fiddy_states[0][0][1:]: 
    query = "FMAC/HPI_"+str(abbv) 
    df = quandl.get(query) 

if main_df.empty: 
    main_df = df 
else: 
    main_df = pd.merge (main_df , df, how = "right") 
print(pd.merge(main_df)) 

und mein Fehler ist:

TypeError: merge() missing 1 required positional argument: 'right' 

was ist los?

Answer 1

main_df.merge(df, how = "right")