如下所示：

import pandas as pdfrom numpy import *import matplotlib.pylab as pltimport copydef read(filename): dat=pd.read_csv(filename,iterator=True) loop = True chunkSize = 1000000 R=[] while loop: try: data = dat.get_chunk(chunkSize) data=data.loc[:,'B':'C'] # 切片 data=data[data.B==855] #条件选择 data['C']=pd.to_datetime(data['C']) # 转换成时间格式 data=data.set_index(['C']) # 设置索引 data.loc[:,'D']=array([1]*len(data)) #增加一列 data=data.resample('D').sum() #按天求和 data=data.loc[:,'D'] #截取 data.fillna(0) #填充缺失值 R.append(data) except StopIteration: loop = False print ("Iteration is stopped.") R.to_csv('855_pay.csv') # 保存def read2(filename): reader=pd.read_csv(filename,iterator=True) loop = True chunkSize = 100000 chunks = [] while loop: try: chunk = reader.get_chunk(chunkSize) chunks.append(chunk) except StopIteration: loop = False print ("Iteration is stopped.") df = pd.concat(chunks, ignore_index=True) return dfdef read3save(filename): dat=pd.read_csv(filename) #data = dat.get_chunk(chunkSize) data=dat.loc[:,'B':'C'] # 切片 data=data[data.B==855]#条件选择 print(shape(data)) data['C']=pd.to_datetime(data['C']) # 转换成时间格式 data=data.set_index(['C'])# 设置索引 if len(data)==0: return data.loc[:,'D']=array([1]*len(data)) #增加一列 data=data.resample('D').sum() #按天求和 data=data.loc[:,'D'] #截取 data.fillna(0) #填充缺失值 data.to_csv('855_pay.csv',mode='a') # 保存def loadDataSet(fileName, delim='\t'): fr = open(fileName) stringArr = [line.strip().split(delim) for line in fr.readlines()] datArr = [list(map(float,line)) for line in stringArr] return mat(datArr)def getShopData(): fr = open('shopInfo.txt') shopID = [line.strip().split('\n') for line in fr.readlines()] # datArr = [list(map(float,line))for line in stringArr] for i in range(1,9): name="user_pay.001.00%d"%i dat=pd.read_csv(name) #data = dat.get_chunk(chunkSize) data=dat.loc[:,'B':'C'] # 切片 for factor in shopID: data=data[data.B==int(str(factor[0]))]#条件选择 print(shape(data)) if len(data)==0: continue data['C']=pd.to_datetime(data['C']) # 转换成时间格式 data=data.set_index(['C'])# 设置索引 data.loc[:,'D']=array([1]*len(data)) #增加一列 data=data.resample('D').sum() #按天求和 data=data.loc[:,'D'] #截取 data.fillna(0) #填充缺失值 s=str(factor[0]) savename='D:\python\data\%s_pay.csv'%s data.to_csv(savename,mode='a') # 保存 del dat print("over")def tset(filename): dat=pd.read_csv(filename) #data = dat.get_chunk(chunkSize) data=dat.loc[:,'B':'C'] # 切片 data=data[data.B==855]#条件选择 print(shape(data)) data['C']=pd.to_datetime(data['C']) # 转换成时间格式 data=data.set_index(['C'])# 设置索引 if len(data)==0: return data.loc[:,'D']=array([1]*len(data)) #增加一列 data=data.resample('D').sum() #按天求和 data=data.loc[:,'D'] #截取 data.fillna(0) #填充缺失值 #data.to_csv('855_pay.csv',mode='a') # 保存 s='my' savename='D:\python\data\%s_pay.csv'%s data.to_csv(savename,mode='a') # 保存 def getShopData2(filename): import csv # fr = open('shopInfo.txt') # shopID = [line.strip().split('\n') for line in fr.readlines()] # datArr = [list(map(float,line))for line in stringArr] #for i in range(1,9): #name="user_pay.001.00%d"%i dat=pd.read_csv(filename) #data = dat.get_chunk(chunkSize) data=dat.loc[:,'B':'C'] # 切片 data['C']=pd.to_datetime(data['C']) # 转换成时间格式 data=data.set_index(['C'])# 设置索引 data.loc[:,'D']=array([1]*len(data)) #增加一列 for i in range(1,2001): d=copy.copy(data) d=d[data.B==i]#条件选择 #print(shape(d)) print(i) if len(d)==0: continue d=d.resample('D').sum() #按天求和 d=d.loc[:,'D'] #截取 d.fillna(0) #填充缺失值 s=str(i) #print(s) savename='D:\python\data2\%s_pay.csv'%s c=open(savename,'a') writer=csv.writer(c) writer.writerow(['C','D']) c.close() d.to_csv(savename,mode='a') # 保存 # del dat print("over")def formatData(): #fr = open('shopInfo.txt') #shopID = [line.strip().split('\n') for line in fr.readlines()] # datArr = [list(map(float,line))for line in stringArr] #data = dat.get_chunk(chunkSize) for i in range(1,2001): s=str(i) print(s) name='D:\python\data2\%s_pay.csv'%s dat=pd.read_csv(name) data['C']=pd.to_datetime(data['C']) # 转换成时间格式 data=data.set_index(['C'])# 设置索引 data=data.resample('D').sum() #按天求和 data.fillna(0) #填充缺失值 savename='D:\python\data3\%s_pay.csv'%s data.to_csv(savename,mode='w') # 保存 del dat print("over")

以上这篇python pandas 对时间序列文件处理的实例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。