将字典数据导出到csv文件

Question

I have created a dictionary data type in Python:

selecteddatas = random.sample(numbers, 100)
    for data in selecteddatas:
        calls = random.choice(range(600))
        a[data] = {'time_stamp': str_now, 'calls': calls}

and I am trying to export it to a csv file, but its not working. Can anyone suggest me how to do it.

Answer 1

A list of dicts with the same keys can be easily converted to a pandas DataFrame. These can then be easily converted to a csv.

import pandas as pd
pd.DataFrame(a).to_csv(filepath,index=False)

Answer 2

Without pandas , using csv.DictWriter :

import random, csv, datetime

selecteddatas = random.sample(list(range(100)), 100)
a = {}
for data in selecteddatas:
    calls = random.choice(range(600))
    a[data] = {'time_stamp': datetime.datetime.now(), 'calls': calls}

with open('data.csv', 'w', newline='') as csvfile:
    writer = csv.DictWriter(csvfile, fieldnames=['time_stamp', 'calls'])

    writer.writeheader()
    for k in a.keys():
        writer.writerow(a[k])

The data.csv contains:

time_stamp,calls
2018-07-24 17:54:01.989054,273
2018-07-24 17:54:01.989059,290
2018-07-24 17:54:01.989062,51
2018-07-24 17:54:01.989064,188
2018-07-24 17:54:01.989067,518
...and so on.