v0.7.0

[0.7.0] - 2026-05-04

Added

• Expanded the built-in unit inventory:

  • frequency feature with hertz units from millihertz through terahertz.
  • chemistry feature with mole units from nanomole through kilomole.
  • electrical feature with current, charge, voltage, resistance, capacitance,
    inductance, magnetic-flux, and magnetic-flux-density units.
  • density feature with SI density units and customary PoundPerCubicFoot.
  • Additional energy units: Picojoule, Nanojoule, WattHour,
    KilowattHour, and customary BritishThermalUnit / Therm.
  • photometry linear SI units: Candela, Lumen, and Lux.
  • Rankine as a linear absolute temperature unit.

• Added local tests for feature-gated length, time, mass, and angular submodules,
  including known-value conversions and proptest round-trips.

• Pressure units in qtty-core::units::pressure (re-exported by qtty::pressure /
  qtty::unit). Always available: Pascal (canonical SI unit), Hectopascal (hPa,
  widely used in observatory site metadata), Millipascal, Kilopascal, Megapascal,
  Gigapascal, and Bar (= 10⁵ Pa). Bidirectional From conversions and
  cross-feature PartialEq / PartialOrd cover all pairs via pressure_units!.
  Named constants PASCAL, HECTOPASCAL, BAR, etc. for quick construction.
  New Pressure dimension alias added to qtty-core::dimension.

• Temperature units in qtty-core::units::temperature (re-exported by
  qtty::temperature / qtty::unit). Always available: Kelvin (SI base unit, the
  only linear-scale thermodynamic temperature unit provided — affine-offset scales
  such as Celsius and Fahrenheit are intentionally omitted). Inventory macro
  temperature_units!, TemperatureUnit marker trait, KELVIN constant.
  New Temperature dimension alias added to qtty-core::dimension.

• Photometry module (qtty-core::units::photometry, behind the photometry
  feature, re-exported by qtty::photometry). Uses a deliberate newtype design (not
  Quantity<U>) for logarithmic quantities where addition is not physically meaningful:

  • Magnitude — stellar magnitude scale (more negative = brighter).
  • SurfaceBrightness — magnitudes per square arcsecond.
  • flux_to_magnitude(flux, zero_point) / magnitude_to_flux(mag, zero_point) —
    typed conversion helpers.
  • band_flux_to_surface_brightness(s10, zero_point) — converts S10 surface flux
    density to a SurfaceBrightness magnitude.
  • s10_to_surface_brightness(flux, zero_point) — typed variant accepting a typed
    S10s quantity and returning SurfaceBrightness; requires radiometry feature.

• Angular wrap helpers on Quantity<U> for any U: AngularUnit:

  • wrap_to_signed_pi() — folds any angle into (−π, +π] (i.e. (−180°, +180°]).
  • wrap_to_unsigned_pi() — folds any angle into [0, 2π) (i.e. [0°, 360°)).
  • fold_to_pi() — folds any angle into [0, π] (i.e. [0°, 180°]), useful for
    unsigned angular separations.

• Typed square root (UnitSqrt trait, qtty-core):

  • UnitSqrt — implemented automatically for Prod<U, U> (a unit multiplied by
    itself, i.e. a squared unit).
  • Quantity<Prod<U, U>, S>::sqrt() — returns Quantity<U, S> with the correct
    halved dimension; the result type is inferred from the input unit, so no
    annotation is needed at the call site.
  • Re-exported from qtty as qtty::UnitSqrt.

• Radiometry additions (extending the initial radiometry feature):

  • PhotonPerSquareCentimeterNanosecondSteradian (ph·cm⁻²·ns⁻¹·sr⁻¹) photon
    radiance unit, matching the NSB/darknsb pipeline output convention.
  • spectral_radiance_to_photon_radiance_ns_nm(energy_radiance, lambda) — converts
    SI spectral energy radiance (W·m⁻²·sr⁻¹·nm⁻¹) to spectral photon radiance
    in the NSB/SkyCalc optical convention (ph·cm⁻²·ns⁻¹·sr⁻¹·nm⁻¹) using the
    exact 1 / (h · c) constant.

• Solid-angle units in qtty-core::units::solid_angle (re-exported by
  qtty::solid_angle / qtty::unit). Always available: SquareDegree
  (canonical), Steradian, SquareMilliradian. Behind astro:
  SquareArcminute, SquareArcsecond. Bidirectional From conversions and
  cross-feature PartialEq / PartialOrd cover all pairs. New
  SolidAngle = Dim<…, A=P2> dimension alias added to qtty-core::dimension.

• radiometry feature (qtty-core, forwarded by qtty, implies
  fundamental-physics) introducing qtty_core::units::radiometry with:

  • Radiance / SpectralRadiance / PhotonRadiance /
    SpectralPhotonRadiance / InverseSolidAngle dimension aliases.
  • SI and CGS unit markers: WattPerSquareMeterSteradian,
    ErgPerSecondSquareCentimeterSteradian, the per-metre / per-nanometre /
    per-ångström spectral-radiance markers, and the ph·… / ph·cm⁻²·s⁻¹·sr⁻¹,
    ph·cm⁻²·ns⁻¹·sr⁻¹, ph·cm⁻²·s⁻¹·sr⁻¹·Å⁻¹, ph·cm⁻²·s⁻¹·sr⁻¹·nm⁻¹
    photon-radiance markers.
  • S10 ("10th-magnitude stars per square degree") on InverseSolidAngle,
    matching the Leinert et al. zodiacal-light tables.
  • erg_to_photon(spectral_energy_radiance, lambda) typed helper using the
    exact 1 / (h · c) constant ≈ 5.034 × 10⁷ ph / (erg · Å).

Changed

• qtty-ffi full linear unit coverage — the stable FFI registry now
  exports every linear unit family exposed by qtty's all-units feature,
  including pressure, solid angle, temperature, radiometry, photometric SI
  units, frequency, chemistry, electrical, and density. Existing discriminants
  remain stable; new dimensions were appended with explicit DimensionId
  values 11 through 32 and new 11xxxx–32xxxx discriminant ranges.

• qtty-ffi energy inventory parity — added the missing Picojoule,
  Nanojoule, WattHour, KilowattHour, BritishThermalUnit, and Therm
  FFI unit IDs so the ABI now matches the Rust energy module exactly.

• qtty-ffi release line — ABI version now reports 700
  (qtty_ffi_version() == 700) for the 0.7.0 release.

• Breaking: corrected public SI aliases so pressure::MPa now means
  Megapascal instead of Millipascal; use MilliPa for millipascal. Also
  added the expected force::MN alias for Meganewton.

• radiometry module now follows the standard qtty unit-module architecture:

  • Per-dimension marker traits (RadianceUnit, SpectralRadianceUnit,
    PhotonRadianceUnit, SpectralPhotonRadianceUnit, InverseSolidAngleUnit).
  • Per-dimension inventory macros (radiance_units!, spectral_radiance_units!,
    photon_radiance_units!, spectral_photon_radiance_units!,
    inverse_solid_angle_units!) with bidirectional From conversions and
    cross-unit-ops PartialEq / PartialOrd within each dimension group.
  • All 13 unit markers registered as BuiltinUnit and covered by
    assert_units_are_builtin compile-time drift checks.
  • Unit markers re-exported from qtty::unit (e.g. qtty::unit::S10,
    qtty::unit::WattPerSquareMeterSteradian); quantity aliases generated at the
    qtty crate root (e.g. qtty::S10s, qtty::WattsPerSquareMeterSteradian)
    when the radiometry feature is enabled.