在Python中将嵌套的字典打印为CSV

Question

I am parsing certain text files and keeping track of a number of programs, software versions, and counts of those versions' occurrences, in the following structure:

{Excel: {'1.2.1':2, '2.1.1':55, '3.4.5':12},
 Adobe: {'1.1.1':4, '5.4.4':12, '4'3.3':8}[...]}

etc.

How can I print this neatly to CSV so that the output would look like this:

Program,Version,Count
Excel,1.2.1,2
Excel,2.1.1,55
Excel,3.4.5,12
Adobe,1.1.1,4
Adobe,5.4.4,12
Adobe,4.3.3,8

I have done a lot of searching and haven't been able to find exactly what I need. Any help is appreciated!

Edit:

Here is what I have tried, which I think comes close, but isn't right based on the output I get:

for prod,version in products.iteritems():
    for p in prod:
        for v in version:
            outfile.write('%s,%s,%d\n' % (p,v,version[v]))

where products is the name of the outer dict.

Thanks.

Answer 1

The hacky way:

def print_csv_data(data):
  with open('my_output', 'w') as f:
     f.write('Program,Version,Count')
     for k, v in data.iteritems():
        for id, count in v.iteritems():
           f.write(k+','+id+','+count)

I'd recommend looking at the CSV module though for better use, as the above approach can easily break your document if your ids or program names contain commas.

import csv

with open('output.csv', 'w') as csvfile:
    fieldnames = ['Program', 'Version', 'Count']
    writer = csv.DictWriter(csvfile, fieldnames=fieldnames)
    writer.writeheader()
    for k, v in data.iteritems():
        for id, count in v.iteritems():
           f.write({'Program':k, 'Version':id, 'Count':count})