python读写csv文件并增加行列的实例代码

            
# -*- coding: utf-8 -*-
"""
Created on Thu Aug 17 11:28:17 2017
@author: Shawn Yuen
"""
import csv
d = list(range(38685))
with open('./kinetics_test.csv') as f1:
 f_csv = csv.DictReader(f1)
 for i, row in enumerate(f_csv):
 #print(row)
 key1 = 'label'
 value1 = 'test'
 row[key1] = value1
 key2 = 'is_cc'
 value2 = '0'
 row[key2] = value2
 d[i] = row
f1.close()
headers = ['label', 'youtube_id', 'time_start', 'time_end', 'split', 'is_cc']
with open('./kinetics_test_new_.csv', 'w') as f:
 f_csv = csv.DictWriter(f, headers)
 f_csv.writeheader()
 f_csv.writerows(d)
f.close()
with open('./kinetics_test_new_.csv','rt') as fin:
 lines=''
 for line in fin:
 if line!='\n':
  lines+=line
with open('./kinetics_test_new.csv','wt')as fout:
 fout.write(lines)
          

            
import pandas as pd
#任意的多组列表
a = [1,2,3]
 b = [4,5,6] 
#字典中的key值即为csv中列名
dataframe = pd.DataFrame({'a_name':a,'b_name':b})
#将DataFrame存储为csv,index表示是否显示行名，default=True
 dataframe.to_csv("test.csv",index=False,sep=',')
 a_name b_name
 0 1 4
 1 2 5
 2 3 6
          

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

            
import csv
#python2可以用file替代open
 with open("test.csv","w") as csvfile: 
 writer = csv.writer(csvfile)
 #先写入columns_name
 writer.writerow(["index","a_name","b_name"])
 #写入多行用writerows
 writer.writerows([[0,1,3],[1,2,3],[2,3,4]])

 index a_name b_name
 0 1 3
 1 2 3
 2 3 4
          

            
import csv
 with open("test.csv","r") as csvfile:
 reader = csv.reader(csvfile)
 #这里不需要readlines
 for line in reader:
  print line