Write dictionary of lists to a CSV file

Question

I\'m struggling with writing a dictionary of lists to a .csv file.

This is how my dictionary looks like:

dict[key1]=[1,2,3]
dict[key2]=[4,5,6]
dict[k         


        

Answer 1

If you don't care about the order of your columns (since dictionaries are unordered), you can simply use zip():

d = {"key1": [1,2,3], "key2": [4,5,6], "key3": [7,8,9]}
with open("test.csv", "wb") as outfile:
   writer = csv.writer(outfile)
   writer.writerow(d.keys())
   writer.writerows(zip(*d.values()))

Result:

key3    key2    key1
7       4       1
8       5       2
9       6       3

If you do care about order, you need to sort the keys:

keys = sorted(d.keys())
with open("test.csv", "wb") as outfile:
   writer = csv.writer(outfile, delimiter = "\t")
   writer.writerow(keys)
   writer.writerows(zip(*[d[key] for key in keys]))

Result:

key1    key2    key3
1       4       7
2       5       8
3       6       9