import pandas as pdfrom pandas import DataFrame,Seriesimport sysimport numpy as npdf = pd.read_csv('E:/Python for Data Analysis/pydata-book-master/ch06/ex1.csv')dfpd.read_table('E:/Python for Data Analysis/pydata-book-master/ch06/ex1.csv',sep =',') # read_table需要指定分隔符pd.read_csv('E:/Python for Data Analysis/pydata-book-master/ch06/ex2.csv',header = None) # 讀取沒有標(biāo)題行的pd.read_csv('E:/Python for Data Analysis/pydata-book-master/ch06/ex2.csv',names=['a','b','c','d','message'])# 指定列名names = ['a','b','c','d','message']pd.read_csv('E:/Python for Data Analysis/pydata-book-master/ch06/ex2.csv',names= names,index_col='message')#把message列作為索引parsed = pd.read_csv('pydata-book-master/ch06/csv_mindex.csv',index_col=['key1','key2'])# 層次化的索引parsed# 使用正則表達(dá)式作為read_table的分隔符list(open('pydata-book-master/ch06/ex6.csv'))result = pd.read_table('pydata-book-master/ch06/ex6.csv',sep='/s+')resultpd.read_csv('pydata-book-master/ch06/ex4.csv',skiprows=[0,2,3]) # 跳過指定的行result = pd.read_csv('pydata-book-master/ch06/ex5.csv')resultresult = pd.read_csv('pydata-book-master/ch06/ex5.csv',na_values=['NULL'])result# 使用一個字典為各列指定不同的NA標(biāo)記的值sentinels = {'message':['foo','NA'],'someting':['two']}pd.read_csv('pydata-book-master/ch06/ex5.csv',na_values=sentinels)#逐塊讀取文本文件result = pd.read_csv('pydata-book-master/ch06/ex6.csv')resultpd.read_csv('pydata-book-master/ch06/ex5.csv',nrows=5) # 只讀取前五行chunker = pd.read_csv('pydata-book-master/ch06/ex5.csv',chunksize=1000) #分成1000塊chunkertot = Series([]) # 定義一個Series來保存后面的數(shù)字for piece in chunker : tot = tot.add(piece['key'].value_counts(),fill_value = 0)tot = tot.order(ascending=False)tot[:10]# 將數(shù)據(jù)寫出到文本格式data = pd.read_csv('pydata-book-master/ch06/ex5.csv')datadata.to_csv('pydata-book-master/ch06/out.csv')data.to_csv(sys.stdout,sep='|') #以指定的分隔符輸出data.to_csv(sys.stdout,na_rep='NULL') # 缺失值在結(jié)果中表示為空白符,也可以自己指定對應(yīng)的符號# 不輸出行列的標(biāo)簽data.to_csv(sys.stdout,index=False,header=False)data.to_csv(sys.stdout,index=False,cols=['a','b','c']) # 只寫出一部分列并且指定列排序dates = pd.date_range('1/1/2000',periods=7)ts = Series(np.arange(7),index=dates)ts.to_csv('pydata-book-master/ch06/tseries.csv') # Series to_csv方法
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