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

//! Decimal arbitrary-base logarithm algorithm family.
//!
//! One algorithm: `LnDivide` -- `log(self, base) = ln(self) / ln(base)`.
//! The per-`(N, SCALE)` realisation lives in
//! [`log_ln_divide`](crate::algos::log::log_ln_divide):
//!
//! - the narrow tiers (D18, D38) route through the composition kernels in
//!   that module -- D18 widens to D38, runs its log, and narrows back; D38
//!   calls the `ln::ln_series_2limb` log kernel directly;
//! - the wide tiers route through the per-tier `log_strict_with_kernel` /
//!   `log_approx_with_kernel` free functions emitted by
//!   `decl_wide_transcendental!` (the real Ziv-escalating computation),
//!   which already live outside the policy in `crate::types::widths`.
//!
//! The per-`(N, SCALE)` choice lives in [`crate::policy::log`], which
//! delegates *down* to these kernels.
//!
//! Variants:
//!
//! - [`log_ln_divide`] -- the production `ln(x)/ln(b)` kernel.
//! - [`log_schoolbook`] -- correctness reference: naive `ln(x)/ln(b)`
//!   using the schoolbook ln. Registered as the unrouted
//!   `Algorithm::Schoolbook` variant.

pub(crate) mod log_ln_divide;
/// Schoolbook base-b logarithm -- naive `ln(x)/ln(b)` composition,
/// correctness reference. Registered as the unrouted `Algorithm::Schoolbook`
/// arm; not connected to `select`.
pub(crate) mod log_schoolbook;