# polyeval

> Evaluate polynomials.

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## Contents

This crate provides four macros (`horner!`, `horner_fma!`, `estrin!`, and `estrin_fma!`) to evaluate
a polynomial using either [Horner's method][Horner] or [Estrin's scheme][Estrin].
The `_fma` variants use "fused multiply-add" instructions where applicable.

It provide also two functions (`horner` and `horner_array`) that work with slices and arrays respectively.

The crate can be `no-std`; the features `std` (enabled by default) and `libm` are passed through to `num-traits`.

[Horner]: https://en.wikipedia.org/wiki/Horner%27s_method
[Estrin]: https://en.wikipedia.org/wiki/Estrin%27s_scheme

## Other crates

On <https://crates.io> there are several crates related to polynomial evaluation:

- [`horner`](https://crates.io/crates/horner): provides two functions to evaluate polynomials of known and unknown order;
- [`horner-eval`](https://crates.io/crates/horner-eval): provides a macro to evaluate polynomials with known coefficients and a function to evaluate polynomials of unknown order;
- [`fast_polynomial`](https://crates.io/crates/fast_polynomial): provides two functions to evaluate polynomials of known and unknown order, implementing a hybrid Estrin's/Horner's method exploiting instruction-level parallelism;
- [`polynomen`](https://crates.io/crates/polynomen): general arithmetic with polynomials (possibly incomplete?);
- [`horny`](https://crates.io/crates/horny) and [`horny_macro`](https://crates.io/crates/horny) are "Reserved for future use (seriously)", but are completely empty and haven't received an update in 3+ years.