[SOLVED] Write dict to csv with integers as keys

Write dict to csv with integers as keys

I have a dict with epoch times as keys. It looks like this:

my_dict = {199934234: "val1", 1999234234: "val2"}

When trying to write it to a csv, I get the error "iterable expected, not int". There is no problem, however, when using regular keys.

import csv

with open('my_file.csv', 'w', newline='') as csvfile:
writer = csv.writer(csvfile)
writer.writerows(my_dict)

I want to write it to a csv so that I can load it at a later point again as a dictionary so that I can update it ... and then write it to a csv again. The csv will be accessed by my website later on.

What would be the best solution to do this? In any other case I would use rrd but in this case I do not have irregular update times.

Solution

The function treats the dictionary as an iterable from which it wants to get other iterables (i.e., the rows).

If you iterate a dictionary, you get only the keys:

for item in my_dict:
    print(item)

199934234
1999234234

Instead, you want an iterable containing your rows. You can use my_dict.items() for that:

print(my_dict.items())

dict_items([(199934234, 'val1'), (1999234234, 'val2')])

So:

import csv

with open('my_file.csv', 'w', newline='') as csvfile:
    writer = csv.writer(csvfile)
    writer.writerows(my_dict.items())

# File content.
199934234,val1
1999234234,val2