仅将元组列表中的值打印到 csv 文件

Question

我有一个可以运行的小程序，但不是我想要的。

上半部分工作正常。

写（下）一半确实有效，但我感兴趣的是值在元组中。没有别的。

我的代码：

import json
import csv

jsonfile = "f:\mark\python\data.json"

with open(jsonfile, "r") as jfile:
    jfile_decode = json.load(jfile)
    # Create a list of tuples with a list comprehension
    jlist = [[(k, v) for k, v in d.items() if k in ['city', 'state', 'population', 'rank']] for d in jfile_decode]
    # print(jlist)  - Just for testing to make sure the output is what I wanted -


outputfile = "f:\mark\python\data.csv"
with open(outputfile, 'w') as f:
    csv_out = csv.writer(f, delimiter=' ')
    csv_out.writerow(['city', 'state', 'population', 'rank'])
    for row in jlist:
        csv_out.writerow(row)

我目前得到的输出：

city state population rank

"('city', 'New York')" "('population', '8405837')" "('rank', '1')" "('state', 'New York')"

"('city', 'Los Angeles')" "('population', '3884307')" "('rank', '2')" "('state', 'California')"

"('city', 'Chicago')" "('population', '2718782')" "('rank', '3')" "('state', 'Illinois')"

"('city', 'Houston')" "('population', '2195914')" "('rank', '4')" "('state', 'Texas')"

我想要的是：（只是元组值。没有别的）

city state population rank

'New York' 'New York' '8405837' '1'

'Los Angeles' 'California' '3884307' '2'

Answer 1

你可以评估字符串，并得到你想要的元素：

outputfile = "f:\mark\python\data.csv"
with open(outputfile, 'w') as f:
    csv_out = csv.writer(f, delimiter=' ')
    csv_out.writerow(['city', 'state', 'population', 'rank'])
    for row in jlist:
        csv_out.writerow(" ".join([col[1] for col in row]))

Edit To erase the double quotes inside the strings use .strip('!"'):

print(" ".join([col[1].strip('!"') for col in row]))

一个例子：

big_tuple = [{'city': 'New York', 'growth_from_2000_to_2013': '4.8%', 'latitude': 40.7127837, 'longitude': -74.0059413, 'population': '8405837', 'rank': '1', 'state': 'New York'},{'city': 'Los Angeles', 'growth_from_2000_to_2013': '4.8%', 'latitude': 34.0522342, 'longitude': -118.2436849, 'population': '3884307', 'rank': '2', 'state': 'California'}]

jlist = [[(k, v) for k, v in d.items() if k in ['city', 'state', 'population', 'rank']] for d in big_tuple]

for row in jlist:
    print(" ".join([col[1] for col in row]))

结果

New York 8405837 1 New York 
Los Angeles 3884307 2 California

仅将元组列表中的值打印到 csv 文件

Print values only in list of tuples to csv file

csv

tuples

list

python-3.6