Add rounding versions of size methods on Count

[itsibitzi]

Why?

When estimating the size of a set it makes sense that you'd want an unsigned integer number value. I've kept the ones that return a real in case.

How?

Rename size methods to size_real and size_with_sketch_real. Add integer-returning size and size_with_sketch methods that round the floating-point estimates. Update all usages in test to call the new methods. Specifically, there are tests that assert that the estimates returned are a specific real value. It is useful that these stay reals because it's possible that if the hashing function changes then we might end up with the same rounded integer but a different real value and I think its good that we know the hash has changed?

Added some debug assertions to panic if the math ever goes awry.

Open Questions

I'm not super in love with the _real affix. _f32 feels a bit technical? Maybe _decimal? _estimate? _exact? _exact_estimate?

[Copilot]

Pull Request Overview

This PR refactors the Count trait to provide both real-valued and integer-returning size estimation methods. The changes rename existing methods to *_real variants and introduce new integer-returning methods that round the floating-point estimates.

• Renamed size() and size_with_sketch() to *_real variants that return f32
• Added new size() and size_with_sketch() methods that return usize by rounding the real values
• Added debug assertions to validate that floating-point estimates are finite, non-negative, and within usize range

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
crates/geo_filters/src/lib.rs	Updated trait definition with new method signatures and added debug assertion helper
crates/geo_filters/src/evaluation/simulation.rs	Updated trait implementations to call size_real() instead of size()
crates/geo_filters/src/evaluation/hll.rs	Renamed method implementations from size to size_real and size_with_sketch to size_with_sketch_real
crates/geo_filters/src/distinct_count.rs	Updated method implementations and test calls to use size_real()
crates/geo_filters/src/diff_count.rs	Updated method implementations and test calls to use size_real()
crates/geo_filters/src/config.rs	Updated test code to call size_real() instead of size()

[itsibitzi]

Lovely, the

#[doc = include_str!("../README.md")]
#[cfg(doctest)]
pub struct ReadmeDocTests;

code caught a regression in the README :)

[aneubeck]

why the suffix real?
Isn't a f32 suffix usually used in rust?

[aneubeck]

while size_f32 is technical, it is also pretty clear what you will get :)

[itsibitzi]

I guess I wanted to encode the semantics relating to the use of the function rather than the technical implementation.

I'll just go with size_f32 so we can sidestep the bike shedding :)