python - Merge multiple DataFrames in an efficient manner -


i have plenty of dataframes need merged axis=0, it's important find fast way op.

so far, try merge , append, these functions need assignment after merging df = df.append(df2) , become slower , slower, there method can merge in place , more efficient?

assuming dataframes have same index, can use pd.concat:

in [61]: df1 out[61]:     0  1  in [62]: df2 out[62]:     b 0  2

create list of dataframes:

in [63]: df_list = [df1, df2]

now, call pd.concat:

in [64]: pd.concat(df_list, axis=1) out[64]:      b 0  1  2

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