python - When slicing a 1 row pandas dataframe the slice becomes a series -

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why when slice pandas dataframe containing 1 row, slice becomes pandas series? how can keep dataframe?

df=pd.dataframe(data=[[1,2,3]],columns=['a','b','c']) df out[37]:      b  c 0  1  2  3   a=df.iloc[0]  out[39]:     1 b    2 c    3 name: 0, dtype: int64

to avoid intermediate step of re-converting dataframe, use double brackets when indexing:

a = df.iloc[[0]] print(a)     b  c 0  1  2  3

speed:

%timeit df.iloc[[0]] 192 µs per loop  %timeit df.loc[0].to_frame().t 468 µs per loop




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