decimal-scaled 0.5.0

Const-generic base-10 fixed-point decimals (D18/D38/D76/D153/D307 and the half-width tiers up to D1232) with integer-only transcendentals correctly rounded to within 0.5 ULP — exact at the type's last representable place. Deterministic across every platform; no_std-friendly.
Documentation 
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// SPDX-FileCopyrightText: 2026 John Moxley
// SPDX-License-Identifier: MIT OR Apache-2.0

//! Natural-logarithm algorithm family.
//!
//! Narrow tier (D18 / D38) calls the `Fixed` 256-bit intermediate
//! kernels; wide tier (D57 .. D1232) runs the tier-generic `ln_tang` /
//! `*_series` kernels via `crate::policy::ln`.
//! Both tiers route through `crate::policy::ln`.
//!
//! Variants:
//!
//! - [`ln_series_2limb`] -- D38's hand-tuned ln on the 256-bit `Fixed`
//!   intermediate with the configurable working-scale guard. Carries
//!   the four-variant matrix entry points (strict mode + approximation
//!   mode, each with an explicit-rounding sibling).
//! - [`ln_schoolbook`] -- correctness reference: atanh series with binary
//!   exponent split. Registered as the unrouted `Algorithm::Schoolbook` variant.

pub(crate) mod ln_series_2limb;
/// Schoolbook natural logarithm -- atanh series correctness reference.
/// Registered as the unrouted `Algorithm::Schoolbook` arm; not connected
/// to `select`.
pub(crate) mod ln_schoolbook;

/// Tier-generic Tang-style table-driven `ln_strict` kernel, generic over
/// `WideTrigCore`. Collapses the thirteen per-tier Tang ln
/// kernels (D57 .. D1232) into one. The `policy::ln` Tang arms call it
/// with the tier's `Core`, `SCALE`, narrow guard, series cap and
/// narrowing strategy.
#[cfg(feature = "_wide-support")]
pub(crate) mod ln_tang;