Lesson 05-05: Duplicating Lists¶
Learning Target: I can duplicate a list.
Algorithm for Duplicating¶
In order to write a function to modify a list without affecting the original one, we would need to make a copy of it. Although there are shortcuts to make copies of lists, let’s first see how we might do it manually.
We want to start by creating a new, blank list. This ensures that it will have a different reference than the one we’re trying to copy.
old_list = [1,2,3,4]
new_list = [] #this is an empty list
Then we need to manually loop through the old array and ‘copy’ every element into the new array. We can do this by using append()
. We can then look at the IDs and check if they are equal to each other using the following code:
Using the copy.copy()
Function¶
Python also has a built-in copy
library that has a bunch of functions related to copying things. We can use the copy.copy()
function to make a quick copy of a list.
As you can see, this much easier - but it’s important to know how to copy lists anyway!
extend