python - Order dataframe by row -

suppose have following dataframe

      c1  c2 john  4   3 bob   5   7 mary  6   5 carl  5   6 james 4   3 

how can order dataframe have:

carl, mary, bob, john, james

in efficient way?

it arbitrary ordering , might have names stored in variable orderednames

define ordering

arbitrary_ordering = ['carl', 'mary', 'bob', 'john', 'james'] 

option 1
loc

df.loc[arbitrary_ordering] 

option 2
reindex

df.reindex(arbitrary_ordering) 

option 3
reindex_axis

df.reindex_axis(arbitrary_ordering) 

all yield

       c1  c2 carl    5   6 mary    6   5 bob     5   7 john    4   3 james   4   3 

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alternative 1

df.iloc[df.index.to_series().map(arbitrary_ordering.index)] 

alternative 2
pd.categorical

df.index = pd.categorical(df.index, categories=arbitrary_ordering) df.sort_index() 

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time test