--- a/src/norms.rs Sun Apr 27 20:29:43 2025 -0500 +++ b/src/norms.rs Fri May 15 14:46:30 2026 -0500 @@ -2,79 +2,84 @@ Norms, projections, etc. */ -use serde::Serialize; -use std::marker::PhantomData; +use crate::euclidean::*; +use crate::instance::Ownable; +use crate::linops::{ClosedVectorSpace, VectorSpace}; +use crate::mapping::{Instance, Mapping, Space}; use crate::types::*; -use crate::euclidean::*; -use crate::mapping::{Mapping, Space, Instance}; +use serde::{Deserialize, Serialize}; +use std::marker::PhantomData; // // Abstract norms // -#[derive(Copy,Clone,Debug)] +#[derive(Copy, Clone, Debug, Serialize, Deserialize)] /// Helper structure to convert a [`NormExponent`] into a [`Mapping`] -pub struct NormMapping<F : Float, E : NormExponent>{ - pub(crate) exponent : E, - _phantoms : PhantomData<F> +pub struct NormMapping<F: Float, E: NormExponent> { + pub(crate) exponent: E, + _phantoms: PhantomData<F>, } /// An exponent for norms. /// // Just a collection of desirable attributes for a marker type -pub trait NormExponent : Copy + Send + Sync + 'static { +pub trait NormExponent: Copy { /// Return the norm as a mappin - fn as_mapping<F : Float>(self) -> NormMapping<F, Self> { - NormMapping{ exponent : self, _phantoms : PhantomData } + fn as_mapping<F: Float>(self) -> NormMapping<F, Self> { + NormMapping { exponent: self, _phantoms: PhantomData } } } /// Exponent type for the 1-[`Norm`]. -#[derive(Copy,Debug,Clone,Serialize,Eq,PartialEq)] +#[derive(Copy, Debug, Clone, Serialize, Eq, PartialEq)] pub struct L1; impl NormExponent for L1 {} /// Exponent type for the 2-[`Norm`]. -#[derive(Copy,Debug,Clone,Serialize,Eq,PartialEq)] +#[derive(Copy, Debug, Clone, Serialize, Eq, PartialEq)] pub struct L2; impl NormExponent for L2 {} /// Exponent type for the ∞-[`Norm`]. -#[derive(Copy,Debug,Clone,Serialize,Eq,PartialEq)] +#[derive(Copy, Debug, Clone, Serialize, Eq, PartialEq)] pub struct Linfinity; impl NormExponent for Linfinity {} /// Exponent type for 2,1-[`Norm`]. /// (1-norm over a domain Ω, 2-norm of a vector at each point of the domain.) -#[derive(Copy,Debug,Clone,Serialize,Eq,PartialEq)] +#[derive(Copy, Debug, Clone, Serialize, Eq, PartialEq)] pub struct L21; impl NormExponent for L21 {} /// Norms for pairs (a, b). ‖(a,b)‖ = ‖(‖a‖_A, ‖b‖_B)‖_J /// For use with [`crate::direct_product::Pair`] -#[derive(Copy,Debug,Clone,Serialize,Eq,PartialEq)] +#[derive(Copy, Debug, Clone, Serialize, Eq, PartialEq)] pub struct PairNorm<A, B, J>(pub A, pub B, pub J); impl<A, B, J> NormExponent for PairNorm<A, B, J> -where A : NormExponent, B : NormExponent, J : NormExponent {} - +where + A: NormExponent, + B: NormExponent, + J: NormExponent, +{ +} /// A Huber/Moreau–Yosida smoothed [`L1`] norm. (Not a norm itself.) /// /// The parameter γ of this type is the smoothing factor. Zero means no smoothing, and higher /// values more smoothing. Behaviour with γ < 0 is undefined. -#[derive(Copy,Debug,Clone,Serialize,Eq,PartialEq)] -pub struct HuberL1<F : Float>(pub F); -impl<F : Float> NormExponent for HuberL1<F> {} +#[derive(Copy, Debug, Clone, Serialize, Eq, PartialEq)] +pub struct HuberL1<F: Float>(pub F); +impl<F: Float> NormExponent for HuberL1<F> {} /// A Huber/Moreau–Yosida smoothed [`L21`] norm. (Not a norm itself.) /// /// The parameter γ of this type is the smoothing factor. Zero means no smoothing, and higher /// values more smoothing. Behaviour with γ < 0 is undefined. -#[derive(Copy,Debug,Clone,Serialize,Eq,PartialEq)] -pub struct HuberL21<F : Float>(pub F); -impl<F : Float> NormExponent for HuberL21<F> {} - +#[derive(Copy, Debug, Clone, Serialize, Eq, PartialEq)] +pub struct HuberL21<F: Float>(pub F); +impl<F: Float> NormExponent for HuberL21<F> {} /// A normed space (type) with exponent or other type `Exponent` for the norm. /// @@ -86,27 +91,27 @@ /// /// println!("{}, {} {}", x.norm(L1), x.norm(L2), x.norm(Linfinity)) /// ``` -pub trait Norm<F : Num, Exponent : NormExponent> { +pub trait Norm<Exponent: NormExponent, F: Num = f64> { /// Calculate the norm. - fn norm(&self, _p : Exponent) -> F; + fn norm(&self, _p: Exponent) -> F; } /// Indicates that the `Self`-[`Norm`] is dominated by the `Exponent`-`Norm` on the space /// `Elem` with the corresponding field `F`. -pub trait Dominated<F : Num, Exponent : NormExponent, Elem> { +pub trait Dominated<F: Num, Exponent: NormExponent, Elem> { /// Indicates the factor $c$ for the inequality $‖x‖ ≤ C ‖x‖_p$. - fn norm_factor(&self, p : Exponent) -> F; + fn norm_factor(&self, p: Exponent) -> F; /// Given a norm-value $‖x‖_p$, calculates $C‖x‖_p$ such that $‖x‖ ≤ C‖x‖_p$ #[inline] - fn from_norm(&self, p_norm : F, p : Exponent) -> F { + fn from_norm(&self, p_norm: F, p: Exponent) -> F { p_norm * self.norm_factor(p) } } /// Trait for distances with respect to a norm. -pub trait Dist<F : Num, Exponent : NormExponent> : Norm<F, Exponent> + Space { +pub trait Dist<Exponent: NormExponent, F: Num = f64>: Norm<Exponent, F> + Space { /// Calculate the distance - fn dist<I : Instance<Self>>(&self, other : I, _p : Exponent) -> F; + fn dist<I: Instance<Self>>(&self, other: I, _p: Exponent) -> F; } /// Trait for Euclidean projections to the `Exponent`-[`Norm`]-ball. @@ -119,44 +124,48 @@ /// /// println!("{:?}, {:?}", x.proj_ball(1.0, L2), x.proj_ball(0.5, Linfinity)); /// ``` -pub trait Projection<F : Num, Exponent : NormExponent> : Norm<F, Exponent> + Sized -where F : Float { +pub trait Projection<F: Num, Exponent: NormExponent>: Ownable + Norm<Exponent, F> { /// Projection of `self` to the `q`-norm-ball of radius ρ. - fn proj_ball(mut self, ρ : F, q : Exponent) -> Self { - self.proj_ball_mut(ρ, q); - self - } - - /// In-place projection of `self` to the `q`-norm-ball of radius ρ. - fn proj_ball_mut(&mut self, ρ : F, q : Exponent); + fn proj_ball(self, ρ: F, q: Exponent) -> Self::OwnedVariant; } -/*impl<F : Float, E : Euclidean<F>> Norm<F, L2> for E { +pub trait ProjectionMut<F: Num, Exponent: NormExponent>: Projection<F, Exponent> { + /// In-place projection of `self` to the `q`-norm-ball of radius ρ. + fn proj_ball_mut(&mut self, ρ: F, q: Exponent); +} + +/*impl<F : Float, E : Euclidean<F>> Norm<L2, F> for E { #[inline] fn norm(&self, _p : L2) -> F { self.norm2() } fn dist(&self, other : &Self, _p : L2) -> F { self.dist2(other) } }*/ -impl<F : Float, E : Euclidean<F> + Norm<F, L2>> Projection<F, L2> for E { +impl<F: Float, E: Euclidean<F> + Norm<L2, F>> Projection<F, L2> for E { #[inline] - fn proj_ball(self, ρ : F, _p : L2) -> Self { self.proj_ball2(ρ) } - - #[inline] - fn proj_ball_mut(&mut self, ρ : F, _p : L2) { self.proj_ball2_mut(ρ) } + fn proj_ball(self, ρ: F, _p: L2) -> Self::OwnedVariant { + self.proj_ball2(ρ) + } } -impl<F : Float> HuberL1<F> { - fn apply(self, xnsq : F) -> F { +impl<F: Float, E: EuclideanMut<F> + Norm<L2, F>> ProjectionMut<F, L2> for E { + #[inline] + fn proj_ball_mut(&mut self, ρ: F, _p: L2) { + self.proj_ball2_mut(ρ) + } +} + +impl<F: Float> HuberL1<F> { + fn apply(self, xnsq: F) -> F { let HuberL1(γ) = self; let xn = xnsq.sqrt(); if γ == F::ZERO { xn } else { if xn > γ { - xn-γ / F::TWO - } else if xn<(-γ) { - -xn-γ / F::TWO + xn - γ / F::TWO + } else if xn < (-γ) { + -xn - γ / F::TWO } else { xnsq / (F::TWO * γ) } @@ -164,25 +173,25 @@ } } -impl<F : Float, E : Euclidean<F>> Norm<F, HuberL1<F>> for E { - fn norm(&self, huber : HuberL1<F>) -> F { +impl<F: Float, E: Euclidean<F> + Normed<F, NormExp = L2>> Norm<HuberL1<F>, F> for E { + fn norm(&self, huber: HuberL1<F>) -> F { huber.apply(self.norm2_squared()) } } -impl<F : Float, E : Euclidean<F>> Dist<F, HuberL1<F>> for E { - fn dist<I : Instance<Self>>(&self, other : I, huber : HuberL1<F>) -> F { +impl<F: Float, E: Euclidean<F> + Normed<F, NormExp = L2>> Dist<HuberL1<F>, F> for E { + fn dist<I: Instance<Self>>(&self, other: I, huber: HuberL1<F>) -> F { huber.apply(self.dist2_squared(other)) } } -// impl<F : Float, E : Norm<F, L2>> Norm<F, L21> for Vec<E> { +// impl<F : Float, E : Norm<L2, F>> Norm<L21, F> for Vec<E> { // fn norm(&self, _l21 : L21) -> F { // self.iter().map(|e| e.norm(L2)).sum() // } // } -// impl<F : Float, E : Dist<F, L2>> Dist<F, L21> for Vec<E> { +// impl<F : Float, E : Dist<F, L2>> Dist<L21, F> for Vec<E> { // fn dist<I : Instance<Self>>(&self, other : I, _l21 : L21) -> F { // self.iter().zip(other.iter()).map(|(e, g)| e.dist(g, L2)).sum() // } @@ -190,20 +199,21 @@ impl<E, F, Domain> Mapping<Domain> for NormMapping<F, E> where - F : Float, - E : NormExponent, - Domain : Space + Norm<F, E>, + F: Float, + E: NormExponent, + Domain: Space, + Domain::Principal: Norm<E, F>, { type Codomain = F; #[inline] - fn apply<I : Instance<Domain>>(&self, x : I) -> F { + fn apply<I: Instance<Domain>>(&self, x: I) -> F { x.eval(|r| r.norm(self.exponent)) } } -pub trait Normed<F : Num = f64> : Space + Norm<F, Self::NormExp> { - type NormExp : NormExponent; +pub trait Normed<F: Num = f64>: Space + Norm<Self::NormExp, F> { + type NormExp: NormExponent; fn norm_exponent(&self) -> Self::NormExp; @@ -214,33 +224,38 @@ // fn similar_origin(&self) -> Self; - fn is_zero(&self) -> bool; + fn is_zero(&self) -> bool { + self.norm_() == F::ZERO + } } -pub trait HasDual<F : Num = f64> : Normed<F> { - type DualSpace : Normed<F>; +pub trait HasDual<F: Num = f64>: Normed<F> + VectorSpace<Field = F> { + type DualSpace: Normed<F> + ClosedVectorSpace<Field = F>; + + fn dual_origin(&self) -> <Self::DualSpace as VectorSpace>::PrincipalV; } /// Automatically implemented trait for reflexive spaces -pub trait Reflexive<F : Num = f64> : HasDual<F> +pub trait Reflexive<F: Num = f64>: HasDual<F> where - Self::DualSpace : HasDual<F, DualSpace = Self> -{ } + Self::DualSpace: HasDual<F, DualSpace = Self::Principal>, +{ +} -impl<F : Num, X : HasDual<F>> Reflexive<F> for X -where - X::DualSpace : HasDual<F, DualSpace = X> -{ } +impl<F: Num, X: HasDual<F>> Reflexive<F> for X where + X::DualSpace: HasDual<F, DualSpace = Self::Principal> +{ +} -pub trait HasDualExponent : NormExponent { - type DualExp : NormExponent; +pub trait HasDualExponent: NormExponent { + type DualExp: NormExponent; fn dual_exponent(&self) -> Self::DualExp; } impl HasDualExponent for L2 { type DualExp = L2; - + #[inline] fn dual_exponent(&self) -> Self::DualExp { L2 @@ -249,17 +264,16 @@ impl HasDualExponent for L1 { type DualExp = Linfinity; - + #[inline] fn dual_exponent(&self) -> Self::DualExp { Linfinity } } - impl HasDualExponent for Linfinity { type DualExp = L1; - + #[inline] fn dual_exponent(&self) -> Self::DualExp { L1 @@ -271,49 +285,50 @@ ($exponent : ty) => { impl<C, F, D> Norm<F, Weighted<$exponent, C>> for D where - F : Float, - D : Norm<F, $exponent>, - C : Constant<Type = F>, + F: Float, + D: Norm<$exponent, F>, + C: Constant<Type = F>, { - fn norm(&self, e : Weighted<$exponent, C>) -> F { + fn norm(&self, e: Weighted<$exponent, C>) -> F { let v = e.weight.value(); assert!(v > F::ZERO); v * self.norm(e.base_fn) } } - impl<C : Constant> NormExponent for Weighted<$exponent, C> {} + impl<C: Constant> NormExponent for Weighted<$exponent, C> {} - impl<C : Constant> HasDualExponent for Weighted<$exponent, C> - where $exponent : HasDualExponent { + impl<C: Constant> HasDualExponent for Weighted<$exponent, C> + where + $exponent: HasDualExponent, + { type DualExp = Weighted<<$exponent as HasDualExponent>::DualExp, C::Type>; fn dual_exponent(&self) -> Self::DualExp { Weighted { - weight : C::Type::ONE / self.weight.value(), - base_fn : self.base_fn.dual_exponent() + weight: C::Type::ONE / self.weight.value(), + base_fn: self.base_fn.dual_exponent(), } } } - impl<C, F, T> Projection<F, Weighted<$exponent , C>> for T + impl<C, F, T> Projection<F, Weighted<$exponent, C>> for T where - T : Projection<F, $exponent >, - F : Float, - C : Constant<Type = F>, + T: Projection<F, $exponent>, + F: Float, + C: Constant<Type = F>, { - fn proj_ball(self, ρ : F, q : Weighted<$exponent , C>) -> Self { + fn proj_ball(self, ρ: F, q: Weighted<$exponent, C>) -> Self { self.proj_ball(ρ / q.weight.value(), q.base_fn) } - fn proj_ball_mut(&mut self, ρ : F, q : Weighted<$exponent , C>) { + fn proj_ball_mut(&mut self, ρ: F, q: Weighted<$exponent, C>) { self.proj_ball_mut(ρ / q.weight.value(), q.base_fn) } } - } + }; } //impl_weighted_norm!(L1); //impl_weighted_norm!(L2); //impl_weighted_norm!(Linfinity); -