Cross-validation: sliding window x expanding window

[wasf84]

Hello, how's everything going?

I've read the entire documentation a few times, searched here in the library's GitHub repository, and couldn't find a direct answer explaining how to perform these two types of cross-validation.

That's why I'm reaching out to you for clarification:

• How do I perform cross-validation using an expanding window on the training data?
• How do I perform cross-validation using a sliding window on the training data? In this strategy, is a new model created for each cross-validation window, or is the same model used?

Thank you so much.
Peace.