Python Pandas-Update a data frame column with values from another

Question

i\'m trying get better at Python and decided to do some analysis on one of my passions. Wrestling! In this case, Japanese Wrestling!

Basically I\'m trying to update valu

Answer 1

So I am going to assume your first dataframe is called df1 and your second one is called df2. Then this would work:

df1 = df1.drop('DMR', 1)
df = merge(df1, df2, on = 'Wrestler')

Just drop DMR from the first dataframe and then merge them on the Wrestler column.

Answer 2

Use map by Series:

df1['DMR'] = df1['Wrestler'].map(df2.set_index('Wrestler')['DMR'])

Or merge with left join and drop for remove column:

df1 = pd.merge(df1.drop('DMR', axis=1), df2, how='left')

---

print (df1)
            Wrestler  Matches       DMR
0      TETSUYA NAITO        9  4.000000
1  HIROSHI TANAHASHI        9  4.111111
2      BAD LUCK FALE        9  3.166667
3        KOTA IBUSHI        9  4.222222
4     ZACK SABRE JR.        9  3.611111
5       HIROOKI GOTO        9  3.694444
6     TOMOHIRO ISHII        9  4.250000
7        TOGI MAKABE        9  3.611111
8        YOSHI-HASHI        9  3.638889
9        YUJI NAGATA        9  4.138889

Notice:

Values in Wrestler column in df2 have to be unique.