python怎麽寫入csv文件

import pandas as pd#任意的多組列表a = [1,2,3]

b = [4,5,6]

#字典中的key值即為csv中列名dataframe = pd.DataFrame({'a_name':a,'b_name':b})#將DataFrame存儲為csv,index表示是否顯示行名，default=Truedataframe.to_csv("test.csv",index=False,sep='')1234567891011

a_name b_name0 1 41 2 52 3 61234

同樣pandas也提供簡單的讀csv方法

import pandas as pddata = pd.read_csv('test.csv')12

會得到壹個DataFrame類型的data，不熟悉處理方法可以參考pandas十分鐘入門

另壹種方法用csv包，壹行壹行寫入

import csv

#python2可以用file替代open

with open("test.csv","w") as csvfile:

writer = csv.writer(csvfile)

#先寫入columns_name

writer.writerow(["index","a_name","b_name"])

#寫入多行用writerows

writer.writerows([[0,1,3],[1,2,3],[2,3,4]])12345678910

index a_name b_name0 1 31 2 32 3 41234

讀取csv文件用reader

import csvwith open("test.csv","r") as csvfile:

reader = csv.reader(csvfile) #這裏不需要readlines

for line in reader:

print line