Tracking Issue (take 2) for `more_float_constants`

[tgross35]

Feature gate: #![feature(more_float_constants)]

This is a tracking issue for additional constants in the {f16, f32, f64, f128}::consts modules.

The original tracking issue was #103883 but we lost the ability to edit the top post.

Public API

// in core::{f16, f32, f64, f128}::consts

/// The golden ratio (φ)
pub const PHI: f64 = 1.618033988749894848204586834365638118_f64;

/// The Euler-Mascheroni constant (γ)
pub const EGAMMA: f64 = 0.577215664901532860606512090082402431_f64;

/// 1/sqrt(π)
pub const FRAC_1_SQRT_PI: f64 = 0.564189583547756286948079451560772586_f64;

/// 1/sqrt(2π)
pub const FRAC_1_SQRT_2PI: f64 = 0.398942280401432677939946059934381868_f64;

/// sqrt(3)
pub const SQRT_3: f64 = 1.732050807568877293527446341505872367_f64;

/// 1/sqrt(3)
pub const FRAC_1_SQRT_3: f64 = 0.577350269189625764509148780501957456_f64;

Steps / History

(Remember to update the S-tracking-* label when checking boxes.)

• ACP: ACP: Add a constant for the golden ratio (phi) to the floating point types libs-team#119
• ACP for FRAC_1_SQRT_2PI Add FRAC_1_SQRT_2PI constant libs-team#383
• Implementation: Add additional float constants #103836
• Add FRAC_1_SQRT_2PI Add FRAC_1_SQRT_2PI constant to f16/f32/f64/f128 #125253
• Add constants for f16 and f128 Add constants for f16 and f128 #123850
• Final comment period (FCP)¹
• Stabilization PR

Unresolved Questions

• Naming of the Euler-Mascheroni constant (gamma)
• Any additional constants?
  • ln(3)
  • FRAC_1_SQRT_2PI or FRAC_1_SQRT_TAU to match the existing TAU
  • SQRT_5 Tracking Issue for more_float_constants #103883 (comment)
  • FRAC_1_SQRT_5 Tracking Issue for more_float_constants #103883 (comment)

Footnotes

1. https://std-dev-guide.rust-lang.org/feature-lifecycle/stabilization.html ↩