How to create multiple class objects and pass arguments with loop in Python?

Question

Here is the set of data,

obj = [[A, B, 2], [D, A, 5] ,[B, C, 3]]

I would like to store this in the following class object

class Map():
 def __init__(self,start,destination,cost):
        self.start = start
        self.destination = destination
        self.cost = cost

I would like to store the obj in something like below with for loop

obj[0].start = A
obj[0].destination = B
obj[0].cost = 2
....
obj[2].start = B
obj[2].destination = C
obj[2].cost = 3

Anyone can help?

chepner · Accepted Answer · 2021-05-13 12:32:58Z

1

A simple list comprehension will do the trick.

obj = [Map(x, y, z) for x, y, z in obj]

You iterate over the original list, unpack each sublist, then call Map on each set of values.

Even simpler, you can let Python unpack the sublists for you.

obj = [Map(*args) for args in obj]

or

import itertools
obj = list(itertools.starmap(Map, obj))

answered May 13, 2021 at 12:32

chepner

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Comments

hjpev · Accepted Answer · 2021-05-13 12:34:50Z

0

Use a list:

maps = []
for object in obj:
    maps.append(Map(object[0], object[1], object[2]))

answered May 13, 2021 at 12:34

hjpev

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