python dataframe unionall

用DataFrame实现类似SQL中的unionall方法,将多个DataFrame合并成一个

方法一:
# -*- coding: UTF-8 -*-
import pandas as pd
df1 = pd.DataFrame([{
  
  'col1':'a', 'col2':1}])
df2 = pd.DataFrame([{
  
  'col1':'b', 'col2':2}])
df3 = pd.DataFrame([{
  
  'col1':'c', 'col2':3}])
lists = [df1, df2, df3]

df = pd.concat(lists)
print df
----------
输出结果:
   co12 col1
0     1    a
0     2    b
0     3    c

方法二:
# -*- coding: UTF-8 -*-
import pandas as pd
df1 = pd.DataFrame([{
  
  'col1':'a', 'col2':1}])
df2 = pd.DataFrame([{
  
  'col1':'b', 'col2':2}])

df = df1.appen(df2)
print df ----------
输出结果:
 co12 col1
0     1    a
0     2    b