[Tutor] Debugging skills (ChatGPT experiment)

[Mats Wichmann]

On 1/15/24 11:39, dn via Tutor wrote:

> User
> Please re-express the answer in simple terms to suit someone who is just 
> starting to learn Python.
> 
> ChatGPT
> Certainly! In the original code, there was a mistake because the list 
> called data was empty, and the code was trying to put values into 
> specific positions that didn't exist yet. To fix this, we use the append 
> method, which adds elements to the end of the list. Here's the corrected 
> version:
> 
> python
> Copy code
> data = []
> 
> for i in range(5):
>      data.append(i)
> 
> Now, it will add each number (i) to the end of the list, and you won't 
> encounter the "IndexError" anymore. It's like building the list step by 
> step.
> 
> User
> Why aren't the specific positions available, or at least accessible, 
> when create a new list in Python? Having created the list, why not write 
> data[ 0 ] = 1?
> 
> ChatGPT
> When you create a new list in Python, it starts out as an empty list 
> with no elements. Unlike some other programming languages, Python 
> doesn't automatically allocate space for specific indices when you 
> create an empty list. Therefore, if you try to access or assign a value 
> to a specific index that doesn't exist yet, you'll encounter an 
> "IndexError."
> 
> In your original code:
> 
> python
> Copy code
> data = []
> for i in range(5):
>      data[i] = i
> 
> You're attempting to assign values to specific indices (0 to 4) in an 
> empty list, but there are no elements at those positions initially.
> 
> On the other hand, when you use the append method:
> 
> python
> Copy code
> data = []
> for i in range(5):
>      data.append(i)
> 
> It dynamically adds elements to the end of the list during each 
> iteration, avoiding the need to access indices that don't exist. This is 
> a common and efficient way to build a list in Python. Once the list is 
> populated, you can access specific positions like data[0] = 1 without 
> any issues.

Well, that's not terrible... maybe there's something to that approach.