From 66819df2547cacd22be2747073704efae04097b9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johanna=20S=C3=B6rng=C3=A5rd?=
 <44257381+JSorngard@users.noreply.github.com>
Date: Sat, 19 Sep 2026 18:21:33 +0200
Subject: [PATCH] Revert "Revert "Simplify polynomial function (#346)" (#348)"

This reverts commit 002a9c3236bd4c96a8604ea72f9f9d72481c52a9.
---
 CHANGELOG.md        | 4 ++++
 src/generic_math.rs | 8 +++-----
 2 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9986faf..adc4d50 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,10 @@
 This file contains the changes to the crate since version 0.1.1.
 This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+
+- Use `reduce` instead of `fold` in the polynomial evaluation function.
+
 ## [2.0.5] - 2026-09-18
 
 - Speed up the Lambert W functions that use Fukushima's method slightly (by up to 10 percent)
diff --git a/src/generic_math.rs b/src/generic_math.rs
index 2226792..6182b14 100644
--- a/src/generic_math.rs
+++ b/src/generic_math.rs
@@ -40,12 +40,10 @@ pub(crate) fn rational_function<T: Float, const N: usize, const D: usize>(
 #[inline]
 fn polynomial<T: Float, const N: usize>(x: T, coefficients: [T; N]) -> T {
     coefficients
-        .iter()
+        .into_iter()
         .rev()
-        .skip(1)
-        .fold(*coefficients.last().unwrap_or(&T::zero()), |acc, &c| {
-            acc * x + c
-        })
+        .reduce(|acc, coefficient| acc * x + coefficient)
+        .unwrap_or(T::zero())
 }
 
 // The functions below are wrappers around the [`num-traits`] crate,