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How to Set Multiple Values of a List in Python [All Method]️

The blog is about How to Set Multiple Values of a List in Python & provides a lot of information to the novice user and the more seasoned user. After completing this guide, you will know how to face these kind problem.
Question: What is the best way to approach this problem? Answer: Check out this blog code to learn how to fix errors How to Set Multiple Values of a List in Python. Question: What is causing this error and what can be done to fix it? Answer: Check out this blog for a solution to your problem.

Suppose we want to simultaneously set multiple elements of a Python list.

arr = [0, 0, 0, 0, 0]

Using a for Loop

We could very well use a conventional for loop.

for i in range(0, 3):
  arr[i] = 1
# [1, 1, 1, 0, 0]

Using Slice Assignments

We can also assign a portion of the list to another list.

To obtain a portion of the list, we can use the slice operator.

arr[0:3] = [1] * 3 
# [1, 1, 1, 0, 0]
arr[0:3] = [0 for i in range(3)]
# [0, 0, 0, 0, 0]

Check the Lengths!

Ensure that the length of both lists are equal, or we could end up in one of these situations.

arr[0:3] = [1] * 6
# [1, 1, 1, 1, 1, 1, 0, 0]

The specified portion of the left-hand list will be replaced, but the remainder of the right-hand list will still be inserted.

Watch Out for References

If we want to fill a list with objects, we can do so following the same method. However, these objects are populated in the list by reference.

obj = {'key': 1}
arr[0:3] = [obj] * 3
# [{'key': 1}, {'key': 1}, {'key': 1}, 0, 0]
arr[0]['key'] = 5
# [{'key': 5}, {'key': 5}, {'key': 5}, 0, 0]

We can bypass this complication by forcing a shallow copy of each object using the copy() method.

obj = {'key': 1}
arr[0:3] = [x.copy() for x in [obj] * 3]
arr[0]['key'] = 5
# [{'key': 5}, {'key': 1}, {'key': 1}, 0, 0]


Now you learned, How you can use & How to Set Multiple Values of a List in Python.
If you need assistance at any stage, please feel free to contact me.

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