How do I create a dictionary from two parallel strings?

Question

I have two text files, which are formatted like so:

foo,bar,etc

the other one is like this:

1,2,3

and I want to put these two text files into one dictionary for Python without having to do each one by hand. I want the output to connect the strings to the numbers. Is there any way of doing this?

Answer 1

keys = first_string.split(',')
values = second_string.split(',')
output_dict = dict(zip(keys, values))

---

>>> first_string = "foo,bar,etc"
>>> second_string = "1,2,3"
>>> keys = first_string.split(',')
>>> values = second_string.split(',')
>>> output_dict = dict(zip(keys, values))
>>> output_dict
{'etc': '3', 'foo': '1', 'bar': '2'}

---

If you want the values to be actual numbers, you can convert them:

values = [int(v) for v in second_string.split(',')]

Answer 2

Assuming you know how to read the data from the file and split the lines into list, and convert them to ints as necessary.

s1 = ['foo', 'bar', 'etc']
n1 = [1, 2, 3]
dict(zip(s1, n1))

yields:

{'bar': 2, 'etc': 3, 'foo': 1}

Notes:

zip() combines your lists:

zip(s1, n1)
[('foo', 1), ('bar', 2), ('etc', 3)]

In case you are not comfortable with creating lists from your lines data, for a given line using split() you can just do

line = line.split(',') #'foo,bar,etc' => ['foo','bar','etc'] / '1,2,3' => ['1','2','3']

and if you want to convert your numeric data to ints use list comprehension:

n1 = [int(n) for n in line] # ['1','2','3'] => [1, 2, 3]

Answer 3

You can read the values and keys directly from the text files, a sample code would be :

import fileinput

keys = []
values = []

for line in fileinput.input(['v.txt']):
    values = values + [int(v) for v in line.split(',')]

for line in fileinput.input(['k.txt']):
    keys = keys + [k.replace("\n","") for k in line.split(',')]

the_dict = dict(zip(keys, values))

I assume that you need the values as integers, and the text files may contain multiple lines but they must contain the same number of elements.