pandas表连接 索引上的合并方法
如下所示：
left1=pd.DataFrame({‘key':[‘a','b','a','a','b','c'],'value':range(6)})
right1=pd.DataFrame({‘group_val':[3.5,7]},index=[‘a','b'])
print(left1)
print(right1)
result=pd.merge(left1,right1,left_on='key',right_index=True)
print(result)
层次化数据的索引
lefth=pd.DataFrame({‘key1':[‘Ohio','Ohio','Ohio','Nevada','Nevada'],
‘key2':[2000,2001,2002,2001,2002],
‘data':np.arange(5)})
print(lefth)
righth=pd.DataFrame(np.arange(12).reshape(6,2),index=[[‘Nevada','Nevada','Ohio','Ohio','Ohio','Ohio'],
[2001,2000,2000,200,2001,2002]])
print(righth)
result=pd.merge(lefth,righth,left_on=[‘key1','key2'],right_index=True)
print(result)
以上代码如果想改为外部连接how=‘outer'就可以了
同时合并双方索引
left2=pd.DataFrame([[1,2],[3,4],[5,6]],index=[‘a','c','e'],columns=[‘Ohio','Neveda']) right2=pd.DataFrame([[7,8],[9,10],[11,12],[13,14]],index=[‘b','c','d','e'],columns=[‘Missouri','Alabma']) print(left2) print(right2) result=pd.merge(left2,right2,how='outer',left_index=True,right_index=True) print(result)
以上这篇pandas表连接索引上的合并方法就是小编分享给大家的全部内容了，希望能给大家一个参考，也希望大家多多支持毛票票。