Vertically concatenate multiple dataframes

Question

So I'm trying to intertwine about 3 dataframes and the result should look like this:

df1

A

D

G

df2

B

E

H

df3

C

F

I

Resulting df:

A

B

C

D

E

F

G

H

I

I tried:

for i in len(df1+df2+df3):
    final_df.append(i)

I want to do this as efficiently as possible and with n dataframes

Answer 1

Referring to Spark unionAll multiple dataframes:

You can simply put all the data frames into a list, and do a unionAll on them, like so:

from functools import reduce
from pyspark.sql import DataFrame

dfs = [df1,df2,df3]
df = reduce(DataFrame.unionAll, dfs)

Answer 2

Use pd.concat:

pd.concat([df1, df2, df3], ignore_index=True)

You can concat as many dataframes as you want.