python教程分享python中csv文件创建、读取及修改等操作实例

import csv     headers = ['学号','姓名','分数']  rows = [('202001','张三','98'),          ('202002','李四','95'),          ('202003','王五','92')]  with open('score.csv','w',encoding='utf8',newline='') as f :      writer = csv.writer(f)      writer.writerow(headers)      writer.writerows(rows)

import csv     headers = ['学号','姓名','分数']  rows = [{'学号':'202001','姓名':'张三','分数':'98'},          {'学号':'202002','姓名':'李四','分数':'95'},          {'学号':'202003','姓名':'王五','分数':'92'}]  with open('score.csv','w',encoding='utf8',newline='') as f :      writer = csv.dictwriter(f,headers)      writer.writeheader()      writer.writerows(rows)

import csv     headers = ['学号,姓名,分数','n']  csv = ['202001,张三,98','n',          '202002,李四,95','n',          '202003,王五,92']  with open('score.csv', 'w',encoding='utf8',newline='') as f:      f.writelines(headers) # write() argument must be str, not tuple      f.writelines(csv)

csv = []  for line in lines:      scores = result[line[0]]      for wav, scores in scores.items():          # csv.append(line[0])          # csv.append(wav)          # csv.append(str(i) for i in scores)          # csv.append('n')          #csv.append(','.join([wav] + [str(i) for i in scores] + 'n'))          csv.append(line[0] +','+ wav )          for i in scores:              csv.append(','+ str(i))          csv.append('n')  with open('task3-result.csv', 'w') as f:      f.writelines(csv)

import pandas as pd      my_matrix = pd.read_csv('score.csv')#,header=none,index_col=none)  '''  header : int or list of ints, default ‘infer',指定行数用来作为列名，数据开始行数。如果文件中没有列名，则默认为0，  index_col : int or sequence or false, default none,用作行索引的列编号或者列名  '''  print(my_matrix)  print(my_matrix.shape)

my_matrix = pd.read_csv('score.csv',header=none,index_col=none)

my_matrix = pd.read_csv('score.csv',header=0,index_col=0)

import pandas as pd   import numpy as np     my_matrix = pd.read_csv('score.csv')#,header=0,index_col=0)  my_matrix = np.array(my_matrix)  print(my_matrix)  print(my_matrix.shape)  print(my_matrix[0][0])

import csv  #读取csv文件  with open('score.csv', "r",encoding='utf8',newline='') as f:  	reader = csv.reader(f)  	for row in reader:  		print(row)

for row in reader:      print(row[0])

import csv  #读取csv文件  with open('score.csv', "r",encoding='utf8',newline='') as f:  	reader = csv.dictreader(f)  	for row in reader:  		print(row)

for row in reader:  	print(row['学号'])