Export a dictionary containing list of tuples to CSV file

Question

I would like to export the following dictionary to csv file:

res_dict = {'A':[(0.1,5),(0.2,6)],'B':[(0.1,3),(0.2,6),(0.6,8),(0.7,9)]

I tried the following code:

    def exportDataToCSV(res):
        with open('XY-data.csv', "wb") as outfile:
            writer = csv.writer(outfile)
            writer.writerow(res.keys())
            for v in res.values():
                writer.writerows(zip(*v))

The problem is, that still I must transpose the data in excel sheet to have required view, as follows:

A              B
0.1,5          0.1,3
0.2,6          0.2,6
               0.6,8
               0.7,9

If possible I would like to avoid using pandas. Any hints?

Thanks

Answer 1

Use itertools.zip_longest

Ex:

import csv
from itertools import zip_longest
res_dict = {'A':[(0.1,5),(0.2,6)],'B':[(0.1,3),(0.2,6),(0.6,8),(0.7,9)]}

def exportDataToCSV(res):
    with open('XY-data.csv', "w") as outfile:
        writer = csv.writer(outfile)
        writer.writerow(res.keys())
        for v in zip_longest(*res.values(), fillvalue=''):
            values = [",".join(map(str,i)) for i in v]
            writer.writerow(values)

exportDataToCSV(res_dict)