CODEWITHSUNDEEP
pythonkeydictionary
aeli
aeli

Reputation: 187

How do I zip keys with individual values in my lists in python?

I am importing a matrix, turning the first row into keys, and turning the rest of the rows into values. I want to zip the keys with each value and put them in a dictionary.

ex:

If I have the following:

k = ['a', 'b']
v = [[1,2], [3,4]]

I want to take each value in v (for x in v) and zip them (k and x) then convert to a dictionary.

Then I will add the dictionaries to a list of dictionaries.

At the end I should have:

dicts = [{'a':1, 'b':2}, {'a':3, 'b':4}]

Right now, I am only zipping my rows with my keys. How do I fix this?

matrix_filename = raw_input("Enter the matrix filename:  ")  
matrix = [i.strip().split() for i in open(matrix_filename).readlines()]  
keys = matrix[0]  
vals= (matrix[1:])  
N=len(vals)  

dicts = []  

for i in range(1,N):  
    for j in range(1,N):  
        vals[i-1][j-1] = int(matrix[i][j])  
        dicts = dict(zip(keys,vals))

Upvotes: 6

Views: 2391

Answers (3)

Jeff Jianfei Guo
Jeff Jianfei Guo

Reputation: 21

I developed a generator-based solution, based on answers from another question.

(duplicate of answer: https://stackoverflow.com/a/69578838/11121534)

This might be helpful when the dict is huge.

def zip_dict(d):
    for vals in zip(*(d.values())):
        yield dict(zip(d.keys(), vals))

Example usage:

d = dict(
    x=[1,3,5,7,9],
    y=[2,4,6,8,10]
)

for t in zip_dict(d):
    print(t)

The result would be:

{'x': 1, 'y': 2}
{'x': 3, 'y': 4}
{'x': 5, 'y': 6}
{'x': 7, 'y': 8}
{'x': 9, 'y': 10}

Upvotes: 0

applicative_functor
applicative_functor

Reputation: 4976

>>> [dict(zip(k, x)) for x in v]
[{'a': 1, 'b': 2}, {'a': 3, 'b': 4}]

Upvotes: 13

Ashwini Chaudhary
Ashwini Chaudhary

Reputation: 250941

using itertools.cycle():

In [51]: from itertools import *

In [52]: cyc=cycle(k)

In [53]: [{next(cyc):y for y in x} for x in v]
Out[53]: [{'a': 1, 'b': 2}, {'a': 3, 'b': 4}]

Upvotes: 3

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