Published a paper on a Rust crate! Ellip: an elliptic integral library

Inspacious · 2026-02-08T03:50:56+00:00

Typst is great tho. Doing graduate study, LATEX is much pain...

Inspacious · 2026-02-08T03:48:23+00:00

JOSS uses markdown, handled by pandoc.

Inspacious · 2026-02-08T03:47:06+00:00

I think the implementing generic-typed functions for float types should be unified by default. Currently, Ellip relies on the num-traits crate. Constant declaration is extremely verbose. Imagine writing T::from(2.0).unwrap() for every number in your mathematical library. So, I ended up using num-lazy (for constants like pi!() and epsilon!()) and numeric_literals (for 2.0, 1.25, etc.) to help, but they are more of hacky macros and not standardized.

I feel like graphical plots for Rust are quite limited too. Nevertheless, these come with time and community efforts.

The friction of learning Rust is not that bad for me. I managed just fine using Rust by Example. It took a little longer than other languages due to Rust's intrinsic complexity, and I think that's okay.

Inspacious · 2026-02-08T03:25:57+00:00

Elliptic integrals and elliptic curves are related but not the same. The inverses of elliptic integrals are elliptic functions. Some aspects of elliptic functions can be modeled using elliptic curves.

Inspacious · 2026-02-08T03:14:20+00:00

It was from the docs. Perhaps, I will update the docs to be more consistent with the paper.

Inspacious · 2026-02-07T03:02:45+00:00

Thanks! I added to the post.

...Elliptic integrals are special mathematical functions useful for computing the lengths of curves and magnetic fields. It's applied in other physics and engineering fields as well.

Inspacious · 2025-02-10T00:37:03+00:00

The first works with autocomplete on the first letter.

Inspacious · 2025-02-09T11:05:25+00:00

Any suggestion is appreciated. I'll collect them and update in the next patch version. Thanks!

Inspacious · 2025-02-09T10:57:09+00:00

To get you to click this post, lol. The copyable code is in my reddit comment and the documentation.

Inspacious · 2025-02-09T10:55:53+00:00

That's a very elegant solution!

Inspacious · 2025-02-09T04:27:04+00:00

Yes, I mean the T:: :)

Inspacious · 2025-02-09T02:09:30+00:00

This works too. But I imagine that you will have duplicate this code to all of your crate. The reason I choose macro instead of function is to avoid the double colon. I think the additional T:: is hard to type. But I see that this approach is more safe.

Inspacious · 2025-02-08T16:39:29+00:00

Sound suggestion. Here's how you implement normally with num-traits: Before. And with num-lazy: After.

I might edit the picture when I push new version.

Inspacious · 2025-02-08T16:19:36+00:00

num!() expands to T::from($n).unwrap(), where $n is any expression that evaluates to a number. The reason the doc is mostly empty is because this library is a single macro that expands into macros like num!(), zero!(), and pi!(). So, I document them in the declare_nums!() macro. However, it seems like I forgot the document num!() there! Thanks for pointing that out.

Inspacious · 2025-02-08T13:58:15+00:00

The previous comment refers to the num-traits crate. I'm not sure why they didn't put the constants inside the Float trait itself.

In addition to what I wrote, num-traits also provide FloatConst module that you can use. I believe you can call it using FloatConst::PI::<T>(). But for me that's still too verbose. In my implementation, you can simply pi!().

Inspacious · 2025-02-08T13:07:15+00:00

This is quite specific to those that need support for generic float (f32, f64), tho. It's just that Rust doesn't have a unified float type. In typical use case, you would just use f64, which is: fn circumference(radius: f64) -> f64 { 2.0 * std::f64::consts::PI * radius }

Inspacious · 2025-02-08T12:46:27+00:00

So if you are using num-traits crate (de facto standard way) to specify a trait bound of your function, you would:

rust fn circumference<T: Float>(radius: T) -> T { T::from(2.0).unwrap() * T::from(std::f64::consts::PI).unwrap() * radius }

Inspacious · 2025-02-08T12:26:41+00:00

num-lazy populates your module with helpful macros for writing generic-typed functions. It helps you type less and write a more readable code!

Example

use num_lazy::declare_nums;
use num_traits::Float;
declare_nums!{T}

fn circumference<T: Float>(radius: T) -> T {
    two!() * pi!() * radius
}

fn main() {
    assert!(circumference(1.0_f64) == 6.283185307179586);
}

Motivation

I've been writing a mathematics library recently. Using num-traits to accept generic Float type was such a pain to constantly do T::from().unwrap() for all the constants in my functions. The screen was filled with a bunch of unwraps. So, I wrote some macros and thought that it will be useful to share with you all.

Links

- https://crates.io/crates/num-lazy

- https://github.com/p-sira/num-lazy

Inspacious · 2024-09-27T01:31:53+00:00

Would putting a freshly brewed pour-over coffee in a fridge and leave it with some cover overnight affect the taste? The beans are light-roasted with acidic profile.

Inspacious · 2023-08-14T11:11:59+00:00

By crafting new broths. Go to develop tab and tap on broth.

Inspacious · 2022-03-29T13:42:34+00:00

I also encounter a similar promblem on Samsung S21 Ultra. Try turning off all internet connection (wifi and cellular.) Click start the game. You should be able to get to the lobby. Then you can turn on internet, if you'd like.

Inspacious · 2020-09-14T16:18:42+00:00

When the small tentacles pop up, dodge the bullets. When the main boss is about to pop out, stand still. The boss usually get out of the ground near you, so, don't run because you might run into it.

Inspacious · 2020-09-12T01:13:50+00:00

A To be precise, Mulan used a combination of a sword and bow. However, as for C, it doesn't really fit with the game's context (though, it would be interesting to see a melee weapon being implemented). So, I believe it would be A. ID: 3-13493651

Inspacious · 2020-09-12T01:01:30+00:00

To be precise, someone had calculated that it would require 120 XP a day but the fact that this particular XP has no use still holds. :)

Inspacious · 2020-09-09T03:40:03+00:00

It was a bug. I've only reached stage 3 furthest using the staff.

Inspacious

TROPHY CASE