检索csv文件的内容作为列表

时间:2013-11-10 14:52:52

标签: python csv python-3.x

检索csv文件内容作为列表的最佳和最优雅的方法是什么?请注意,所需的列(如Country,Area和Population)将自动标识,如下面的程序所示。

with open ('data.csv','r') as infile:
    contents = infile.read().split(',')

with open ('data.csv','r') as infile:
    countries = [item.split(',')[contents.index('Country')] for item in infile]

with open ('data.csv','r') as infile:
    areas = [item.split(',')[contents.index('Area')] for item in infile]

with open ('data.csv','r') as infile:
    populations = [item.split(',')[contents.index('Population')] for item in infile]

print (countries)
print (areas)
print (populations)

以上程序有效,但寻找相当简短易读的程序。

更新: 为了防止某些文件中不存在某些列(例如“国家/地区”)时出现错误,可以通过以下方式改进程序:

countries = [item.split(',')[contents.index('Country')] for item in infile if 'Country' in contents]

如何使用csv模块完成?

1 个答案:

答案 0 :(得分:3)

csv module用于CSV文件:

import csv

countries = []
areas = []
populations = []

with open ('data.csv', newline='') as infile:
    reader = csv.DictReader(infile)
    for row in reader:
        countries.append(row['Country'])
        areas.append(row['Area'])
        populations.append(row['Population'])

DictReader()类自动使用第一行标题作为文件其余部分的键。

或使用:

import csv

with open ('data.csv', newline='') as infile:
    reader = csv.reader(infile)
    next(reader, None)  # skip the header first
    countries, areas, populations = zip(*reader)

如果您拥有3列,国家,地区和人口,则按此顺序。