Convert list to list of dictionaries in python

Question

I have two python lists like the following:

fruits = ["apple", "banana", "guava", "grapes"]  
colour = ["red", "yellow", "green", "black"]

I wish to convert them into a dictionary of the following format:

dictionary = [{"fruit":"apple", "colour":"red"},{"fruit":"banana", "colour":"yellow"}...]

consider providing further details like the code you've already tried etc :) — Jayaram, May 13 '16 at 12:44
Very similary to this: http://stackoverflow.com/questions/4576115/convert-a-list-to-a-dictionary-in-python?rq=1 — Tom Myddeltyn, May 13 '16 at 12:50

Martijn Pieters · Accepted Answer · 2016-05-13T12:46:05.220

10

Zip your fruit and colour lists together using the zip() function, and build a new dictionary from each pair:

[{'fruit': f, 'colour': c} for f, c in zip(fruits, colour)]

This uses a list comprehension to create the list output from a loop.

Demo:

>>> fruits = ["apple", "banana", "guava", "grapes"]
>>> colour = ["red", "yellow", "green", "black"]
>>> [{'fruit': f, 'colour': c} for f, c in zip(fruits, colour)]
[{'colour': 'red', 'fruit': 'apple'}, {'colour': 'yellow', 'fruit': 'banana'}, {'colour': 'green', 'fruit': 'guava'}, {'colour': 'black', 'fruit': 'grapes'}]

edited May 13 '16 at 12:46

answered May 13 '16 at 12:40

Martijn Pieters

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As always a good answer of you! But keep in mind that even Python beginners might not understand zipping of lists or for loops with several variable assignments in a list comprehension... – linusg May 13 '16 at 12:47
2

@linusg: I'm here for follow-up comments, there usually are SO questions and documentation we can point to. – Martijn Pieters May 13 '16 at 12:48

score 0 · Answer 2 · answered May 13 '16 at 12:54

A good solution I found is to use an external CSV file to manage your dictionary for example the dict.csv is the directry of the csv file

import csv
import os

dictionary = os.getcwd() +  r'\dict.csv'
with open(dictionary, mode='r') as infile:
        reader = csv.reader(infile)
        mydict = {rows[0]:rows[1] for rows in reader}

and in the csv file can have first column as fruits second column as color. Easy to modify and manage

Convert list to list of dictionaries in python

2 Answers2