Implementing epsilon function to retrieve EPSILON constant
Hey!
This PR exposes a new `epsilon` function in the `Float` trait so that users can access the `EPSILON` constant on the float types. I figured as this was such a minimal change it was easier to get a PR in offering the change then write up an issue.
For me this is a valuable addition. When writing linear algebra or other optimization routines with generic floats we often want to check if some stopping criteria is reached, often something like: `(a - b).abs() < eps`. Having access to a standard _small value_ would make this a little easier.
Use serde 0.8
I updated `bigint`, `complex`, and `rational` to use `serde 0.8`, and also fixed deserialization and the `serde` feature as such in the `rational` crate (didn't add any tests, but it compiles now).
Similar to https://github.com/rust-num/num/pull/196 for `num/complex`, “`use serde;`” needed to be removed in `num/rational`.
Add a trait for floating-point constants
The pull request is to address issue #194. In order to keep the library organized, I’ve introduced a new trait for the new functionality. The trait is supposed to closely follows the [`consts`](https://doc.rust-lang.org/std/f64/consts/index.html) module from the standard library. There are at least the following three open questions:
1. What should the name of the trait be? Currently, it’s `Constant`; an alternative is `Consts`.
2. What should the names of the getters be? Currently, they are lower-case versions of the constants defined in the `consts` module. Note that `Float` provides `log2` and `log10`, whereas `LOG_2` and `LOG_10` get translated into `log_2` and `log_10`, respectively.
3. Should `Float` require the new trait? Or should it be left up to the user?
Please let me know what you think. Thank you!
Regards,
Ivan
Inline small functions, especially wrappers
We already had `#[inline]` throughout a lot of the code, but notably some
functions which simply wrap inherent methods were not inlined. That means
external references will get a full function call, when they could have been
optimized to as little as one opcode.
This PR inlines all functions that look tiny enough for this to matter.
Fixes#218.
rational: recip bugfix and documentation tweaks
Cherry picked from #210 (minus the `new_raw` stuff), with small additions [in a third commit](32dee9a0c8).
traits: add `to_degrees` and `to_radians` on `Float`
To avoid a breaking change, these have crude default implementations as
well as better implementations for `f32` and `f64` in particular. They
don't use the inherent methods though, because `f32` didn't stabilize
those until Rust 1.7.
Fixes#211
To avoid a breaking change, these have crude default implementations as
well as better implementations for `f32` and `f64` in particular. They
don't use the inherent methods though, because `f32` didn't stabilize
those until Rust 1.7.
Fixes#211
bigint: allow `Sub` to work in-place on the RHS
A new Fibonacci benchmark demonstrates the improvement by using both
addition and subtraction in each iteration of the loop, like #200.
Before:
test fib2_100 ... bench: 4,558 ns/iter (+/- 3,357)
test fib2_1000 ... bench: 62,575 ns/iter (+/- 5,200)
test fib2_10000 ... bench: 2,898,425 ns/iter (+/- 207,973)
After:
test fib2_100 ... bench: 1,973 ns/iter (+/- 102)
test fib2_1000 ... bench: 41,203 ns/iter (+/- 947)
test fib2_10000 ... bench: 2,544,272 ns/iter (+/- 45,183)
A new Fibonacci benchmark demonstrates the improvement by using both
addition and subtraction in each iteration of the loop, like #200.
Before:
test fib2_100 ... bench: 4,558 ns/iter (+/- 3,357)
test fib2_1000 ... bench: 62,575 ns/iter (+/- 5,200)
test fib2_10000 ... bench: 2,898,425 ns/iter (+/- 207,973)
After:
test fib2_100 ... bench: 1,973 ns/iter (+/- 102)
test fib2_1000 ... bench: 41,203 ns/iter (+/- 947)
test fib2_10000 ... bench: 2,544,272 ns/iter (+/- 45,183)
This splits the main arithmetic loops from the final carry/borrow
propagation, and also normalizes the slice lengths before iteration.
This lets the optimizer generate better code for these functions.
Homu
James Lucas
Łukasz Jan Niemier
bluss
Josh Stone
Richard Janis Goldschmidt
Ivan Ukhov
Michael Lamparski
Kent Overstreet
Adam Crume