pandas对数据预处理：对series和dataframe进行各种排序

#coding=utf-8  
import pandas as pd  
import numpy as np  
#以下实现排序功能。  
series=pd.Series([3,4,1,6],index=['b','a','d','c'])  
frame=pd.DataFrame([[2,4,1,5],[3,1,4,5],[5,1,4,2]],columns=['b','a','d','c'],index=['one','two','three'])  
print (frame)  
print (series)  
print ('series通过索引进行排序：')  
print (series.sort_index())  
print ('series通过值进行排序:')  
print (series.sort_values())  
print ('dataframe根据行索引进行降序排序（排序时默认升序，调节ascending参数）：' ) 
print (frame.sort_index(ascending=False))  
print ('dataframe根据列索引进行排序：')  
print (frame.sort_index(axis=1) ) 
print ('dataframe根据值进行排序：' ) 
print (frame.sort_values(by='a'))  
print ('通过多个索引进行排序：'  )
print (frame.sort_values(by=['a','c']) )
#coding=utf-8  
import pandas as pd  
import nu