How to create variables dynamically in Python?

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1

How can you dynamically create variables using python dynamic variable name techniques?

Does anyone have any creative ways of achieving this in Python?

2

I’ve been working with Python for a while, and let me tell you, unless there’s a strong need to create a mess of variable names, it’s generally better to use a dictionary for dynamic variable name creation. With a dictionary, you can dynamically generate keys and associate each key with a value—it’s clean and manageable.

For example:

a = {}
k = 0
while k < 10:
    # Dynamically create key
    key = f"var{k}"
    # Calculate value
    value = k * 2
    a[key] = value
    k += 1

This way, you can easily access the values using their respective keys without cluttering your namespace. Also, it keeps things straightforward and readable for anyone else working with your code.

3

Yeah, Yanisleidi makes a great point about dictionaries. I’ve been in situations where using a collections.defaultdict instead of a regular dictionary added even more flexibility, especially when dealing with default values.

Here’s an example:

from collections import defaultdict

a = defaultdict(int)
k = 0
while k < 10:
    # Dynamically create key
    key = f"var{k}"
    # Calculate value
    value = k * 2
    a[key] = value
    k += 1

With a defaultdict, you don’t need to worry about initializing keys beforehand because it automatically handles missing keys. It’s a subtle yet powerful addition to your toolbox when managing dynamic variable creation.

4

Both approaches above are excellent for maintaining clean and scalable code. That said, if you’re in a situation where you really need to create actual variable names dynamically (though I’d recommend thinking twice before doing this), you can use the exec() function.

Here’s a quick example:

k = 0
while k < 10:
    # Dynamically create variable name
    exec(f"var{k} = {k * 2}")
    k += 1

Now, this directly creates variables like var0, var1, and so on, with their values assigned dynamically. However, a word of caution: this can make your code harder to debug and maintain. Stick to dictionaries or defaultdict if you can, but if you must use this method, handle it carefully.