python读写csv文件方式(创建,追加,覆盖)

import csv
def create_csv():
    path = "aa.csv"
    with open(path,'wb') as f:
        csv_write = csv.writer(f)
        csv_head = ["Good","bad"]
        csv_write.writerow(csv_head)

def write_csv():
    path  = "aa.csv"
    with open(path,'a+') as f:
        csv_write = csv.writer(f)
        data_row = ["1","2"]
        csv_write.writerow(data_row)

def read_csv():
    path = "aa.csv"
    with open(path,"rb") as f:
        csv_read = csv.reader(f)
        for line in csv_read:
            print line

import pandas as pd
a = [[1,2],[3,4]]
data = DataFrame(a,index=['x1', 'x2'],columns=['y1', 'y2'])
path= r'C:\Users\Administrator\Desktop\files'
for i in range(0,4):
    for j in range(0,4):
        x = data.to_csv(os.path.join(path,str(i) + '-' + str(j) + '.txt'),sep='\t',header=None,index=None)