所需模块：:

import numpy as np
import pandas as pd

代码＃：DataFrames连接

concat()函数执行沿轴执行连接操作的所有繁重工作，同时在其他轴上执行索引（如果有）的可选集合逻辑（并集或交集）。

# Python program to concatenate

# dataframes using Panda

# Creating first dataframe

df1 = pd.DataFrame({'A': ['A0', 'A1', 'A2', 'A3'],

'B': ['B0', 'B1', 'B2', 'B3'],

'C': ['C0', 'C1', 'C2', 'C3'],

'D': ['D0', 'D1', 'D2', 'D3']},

index = [0, 1, 2, 3])

# Creating second dataframe

df2 = pd.DataFrame({'A': ['A4', 'A5', 'A6', 'A7'],

'B': ['B4', 'B5', 'B6', 'B7'],

'C': ['C4', 'C5', 'C6', 'C7'],

'D': ['D4', 'D5', 'D6', 'D7']},

index = [4, 5, 6, 7])

# Creating third dataframe

df3 = pd.DataFrame({'A': ['A8', 'A9', 'A10', 'A11'],

'B': ['B8', 'B9', 'B10', 'B11'],

'C': ['C8', 'C9', 'C10', 'C11'],

'D': ['D8', 'D9', 'D10', 'D11']},

index = [8, 9, 10, 11])

# Concatenating the dataframes

pd.concat([df1, df2, df3])