--- a/src/linops.rs Sat Dec 14 09:31:27 2024 -0500 +++ b/src/linops.rs Tue Dec 31 08:30:02 2024 -0500 @@ -4,59 +4,69 @@ use numeric_literals::replace_float_literals; use std::marker::PhantomData; +use serde::Serialize; use crate::types::*; -use serde::Serialize; -pub use crate::mapping::Apply; +pub use crate::mapping::{Mapping, Space}; use crate::direct_product::Pair; +use crate::instance::Instance; +use crate::norms::{NormExponent, PairNorm, L1, L2, Linfinity}; /// Trait for linear operators on `X`. -pub trait Linear<X> : Apply<X, Output=Self::Codomain> - + for<'a> Apply<&'a X, Output=Self::Codomain> { - type Codomain; -} +pub trait Linear<X : Space> : Mapping<X> +{ } /// Efficient in-place summation. #[replace_float_literals(F::cast_from(literal))] -pub trait AXPY<F : Num, X = Self> { +pub trait AXPY<F, X = Self> : Space +where + F : Num, + X : Space, +{ /// Computes `y = βy + αx`, where `y` is `Self`. - fn axpy(&mut self, α : F, x : &X, β : F); + fn axpy<I : Instance<X>>(&mut self, α : F, x : I, β : F); /// Copies `x` to `self`. - fn copy_from(&mut self, x : &X) { + fn copy_from<I : Instance<X>>(&mut self, x : I) { self.axpy(1.0, x, 0.0) } /// Computes `y = αx`, where `y` is `Self`. - fn scale_from(&mut self, α : F, x : &X) { + fn scale_from<I : Instance<X>>(&mut self, α : F, x : I) { self.axpy(α, x, 0.0) } } /// Efficient in-place application for [`Linear`] operators. #[replace_float_literals(F::cast_from(literal))] -pub trait GEMV<F : Num, X, Y = <Self as Linear<X>>::Codomain> : Linear<X> { +pub trait GEMV<F : Num, X : Space, Y = <Self as Mapping<X>>::Codomain> : Linear<X> { /// Computes `y = αAx + βy`, where `A` is `Self`. - fn gemv(&self, y : &mut Y, α : F, x : &X, β : F); + fn gemv<I : Instance<X>>(&self, y : &mut Y, α : F, x : I, β : F); /// Computes `y = Ax`, where `A` is `Self` - fn apply_mut(&self, y : &mut Y, x : &X){ + fn apply_mut<I : Instance<X>>(&self, y : &mut Y, x : I){ self.gemv(y, 1.0, x, 0.0) } /// Computes `y += Ax`, where `A` is `Self` - fn apply_add(&self, y : &mut Y, x : &X){ + fn apply_add<I : Instance<X>>(&self, y : &mut Y, x : I){ self.gemv(y, 1.0, x, 1.0) } } /// Bounded linear operators -pub trait BoundedLinear<X> : Linear<X> { - type FloatType : Float; +pub trait BoundedLinear<X, XExp, CodExp, F = f64> : Linear<X> +where + F : Num, + X : Space, + XExp : NormExponent, + CodExp : NormExponent +{ /// A bound on the operator norm $\|A\|$ for the linear operator $A$=`self`. /// This is not expected to be the norm, just any bound on it that can be - /// reasonably implemented. - fn opnorm_bound(&self) -> Self::FloatType; + /// reasonably implemented. The [`NormExponent`] `xexp` indicates the norm + /// in `X`, and `codexp` in the codomain. + fn opnorm_bound(&self, xexp : XExp, codexp : CodExp) -> F; } // Linear operator application into mutable target. The [`AsRef`] bound @@ -70,16 +80,16 @@ }*/ /// Trait for forming the adjoint operator of `Self`. -pub trait Adjointable<X,Yʹ> : Linear<X> { - type AdjointCodomain; +pub trait Adjointable<X, Yʹ> : Linear<X> +where + X : Space, + Yʹ : Space, +{ + type AdjointCodomain : Space; type Adjoint<'a> : Linear<Yʹ, Codomain=Self::AdjointCodomain> where Self : 'a; /// Form the adjoint operator of `self`. fn adjoint(&self) -> Self::Adjoint<'_>; - - /*fn adjoint_apply(&self, y : &Yʹ) -> Self::AdjointCodomain { - self.adjoint().apply(y) - }*/ } /// Trait for forming a preadjoint of an operator. @@ -89,189 +99,206 @@ /// operator. The space `Ypre` is the predual of its codomain, and should be the /// domain of the adjointed operator. `Self::Preadjoint` should be /// [`Adjointable`]`<'a,Ypre,X>`. -pub trait Preadjointable<X,Ypre> : Linear<X> { - type PreadjointCodomain; - type Preadjoint<'a> : Adjointable<Ypre, X, Codomain=Self::PreadjointCodomain> where Self : 'a; - /// Form the preadjoint operator of `self`. +pub trait Preadjointable<X : Space, Ypre : Space> : Linear<X> { + type PreadjointCodomain : Space; + type Preadjoint<'a> : Adjointable< + Ypre, X, AdjointCodomain=Self::Codomain, Codomain=Self::PreadjointCodomain + > where Self : 'a; + + /// Form the adjoint operator of `self`. fn preadjoint(&self) -> Self::Preadjoint<'_>; } /// Adjointable operators $A: X → Y$ between reflexive spaces $X$ and $Y$. -pub trait SimplyAdjointable<X> : Adjointable<X,<Self as Linear<X>>::Codomain> {} -impl<'a,X,T> SimplyAdjointable<X> for T where T : Adjointable<X,<Self as Linear<X>>::Codomain> {} +pub trait SimplyAdjointable<X : Space> : Adjointable<X,<Self as Mapping<X>>::Codomain> {} +impl<'a,X : Space, T> SimplyAdjointable<X> for T +where T : Adjointable<X,<Self as Mapping<X>>::Codomain> {} /// The identity operator #[derive(Clone,Copy,Debug,Serialize,Eq,PartialEq)] pub struct IdOp<X> (PhantomData<X>); impl<X> IdOp<X> { - fn new() -> IdOp<X> { IdOp(PhantomData) } + pub fn new() -> IdOp<X> { IdOp(PhantomData) } } -impl<X> Apply<X> for IdOp<X> { - type Output = X; +impl<X : Clone + Space> Mapping<X> for IdOp<X> { + type Codomain = X; - fn apply(&self, x : X) -> X { - x + fn apply<I : Instance<X>>(&self, x : I) -> X { + x.own() } } -impl<'a, X> Apply<&'a X> for IdOp<X> where X : Clone { - type Output = X; - - fn apply(&self, x : &'a X) -> X { - x.clone() - } -} - -impl<X> Linear<X> for IdOp<X> where X : Clone { - type Codomain = X; -} - +impl<X : Clone + Space> Linear<X> for IdOp<X> +{ } #[replace_float_literals(F::cast_from(literal))] -impl<F : Num, X, Y> GEMV<F, X, Y> for IdOp<X> where Y : AXPY<F, X>, X : Clone { +impl<F : Num, X, Y> GEMV<F, X, Y> for IdOp<X> +where + Y : AXPY<F, X>, + X : Clone + Space +{ // Computes `y = αAx + βy`, where `A` is `Self`. - fn gemv(&self, y : &mut Y, α : F, x : &X, β : F) { + fn gemv<I : Instance<X>>(&self, y : &mut Y, α : F, x : I, β : F) { y.axpy(α, x, β) } - fn apply_mut(&self, y : &mut Y, x : &X){ + fn apply_mut<I : Instance<X>>(&self, y : &mut Y, x : I){ y.copy_from(x); } } -impl<X> BoundedLinear<X> for IdOp<X> where X : Clone { - type FloatType = float; - fn opnorm_bound(&self) -> float { 1.0 } +impl<F, X, E> BoundedLinear<X, E, E, F> for IdOp<X> +where + X : Space + Clone, + F : Num, + E : NormExponent +{ + fn opnorm_bound(&self, _xexp : E, _codexp : E) -> F { F::ONE } } -impl<X> Adjointable<X,X> for IdOp<X> where X : Clone { +impl<X : Clone + Space> Adjointable<X,X> for IdOp<X> { type AdjointCodomain=X; type Adjoint<'a> = IdOp<X> where X : 'a; + fn adjoint(&self) -> Self::Adjoint<'_> { IdOp::new() } } +impl<X : Clone + Space> Preadjointable<X,X> for IdOp<X> { + type PreadjointCodomain=X; + type Preadjoint<'a> = IdOp<X> where X : 'a; + + fn preadjoint(&self) -> Self::Preadjoint<'_> { IdOp::new() } +} + /// “Row operator” $(S, T)$; $(S, T)(x, y)=Sx + Ty$. pub struct RowOp<S, T>(pub S, pub T); use std::ops::Add; -impl<A, B, S, T> Apply<Pair<A, B>> for RowOp<S, T> +impl<A, B, S, T> Mapping<Pair<A, B>> for RowOp<S, T> where - S : Apply<A>, - T : Apply<B>, - S::Output : Add<T::Output> + A : Space, + B : Space, + S : Mapping<A>, + T : Mapping<B>, + S::Codomain : Add<T::Codomain>, + <S::Codomain as Add<T::Codomain>>::Output : Space, + { - type Output = <S::Output as Add<T::Output>>::Output; + type Codomain = <S::Codomain as Add<T::Codomain>>::Output; - fn apply(&self, Pair(a, b) : Pair<A, B>) -> Self::Output { + fn apply<I : Instance<Pair<A, B>>>(&self, x : I) -> Self::Codomain { + let Pair(a, b) = x.decompose(); self.0.apply(a) + self.1.apply(b) } } -impl<'a, A, B, S, T> Apply<&'a Pair<A, B>> for RowOp<S, T> +impl<A, B, S, T> Linear<Pair<A, B>> for RowOp<S, T> where - S : Apply<&'a A>, - T : Apply<&'a B>, - S::Output : Add<T::Output> -{ - type Output = <S::Output as Add<T::Output>>::Output; + A : Space, + B : Space, + S : Linear<A>, + T : Linear<B>, + S::Codomain : Add<T::Codomain>, + <S::Codomain as Add<T::Codomain>>::Output : Space, +{ } - fn apply(&self, Pair(ref a, ref b) : &'a Pair<A, B>) -> Self::Output { - self.0.apply(a) + self.1.apply(b) - } -} -impl<A, B, S, T, D> Linear<Pair<A, B>> for RowOp<S, T> +impl<'b, F, S, T, Y, U, V> GEMV<F, Pair<U, V>, Y> for RowOp<S, T> where - RowOp<S, T> : Apply<Pair<A, B>, Output=D> + for<'a> Apply<&'a Pair<A, B>, Output=D>, -{ - type Codomain = D; -} - -impl<F, S, T, Y, U, V> GEMV<F, Pair<U, V>, Y> for RowOp<S, T> -where + U : Space, + V : Space, S : GEMV<F, U, Y>, T : GEMV<F, V, Y>, F : Num, Self : Linear<Pair<U, V>, Codomain=Y> { - fn gemv(&self, y : &mut Y, α : F, x : &Pair<U, V>, β : F) { - self.0.gemv(y, α, &x.0, β); - self.1.gemv(y, α, &x.1, β); + fn gemv<I : Instance<Pair<U, V>>>(&self, y : &mut Y, α : F, x : I, β : F) { + let Pair(u, v) = x.decompose(); + self.0.gemv(y, α, u, β); + self.1.gemv(y, α, v, F::ONE); } - fn apply_mut(&self, y : &mut Y, x : &Pair<U, V>){ - self.0.apply_mut(y, &x.0); - self.1.apply_mut(y, &x.1); + fn apply_mut<I : Instance<Pair<U, V>>>(&self, y : &mut Y, x : I) { + let Pair(u, v) = x.decompose(); + self.0.apply_mut(y, u); + self.1.apply_mut(y, v); } /// Computes `y += Ax`, where `A` is `Self` - fn apply_add(&self, y : &mut Y, x : &Pair<U, V>){ - self.0.apply_add(y, &x.0); - self.1.apply_add(y, &x.1); + fn apply_add<I : Instance<Pair<U, V>>>(&self, y : &mut Y, x : I) { + let Pair(u, v) = x.decompose(); + self.0.apply_add(y, u); + self.1.apply_add(y, v); } } - /// “Column operator” $(S; T)$; $(S; T)x=(Sx, Tx)$. pub struct ColOp<S, T>(pub S, pub T); -impl<A, S, T, O> Apply<A> for ColOp<S, T> +impl<A, S, T> Mapping<A> for ColOp<S, T> where - S : for<'a> Apply<&'a A, Output=O>, - T : Apply<A>, - A : std::borrow::Borrow<A>, + A : Space, + S : Mapping<A>, + T : Mapping<A>, { - type Output = Pair<O, T::Output>; + type Codomain = Pair<S::Codomain, T::Codomain>; - fn apply(&self, a : A) -> Self::Output { - Pair(self.0.apply(a.borrow()), self.1.apply(a)) + fn apply<I : Instance<A>>(&self, a : I) -> Self::Codomain { + Pair(self.0.apply(a.ref_instance()), self.1.apply(a)) } } -impl<A, S, T, D> Linear<A> for ColOp<S, T> +impl<A, S, T> Linear<A> for ColOp<S, T> where - ColOp<S, T> : Apply<A, Output=D> + for<'a> Apply<&'a A, Output=D>, -{ - type Codomain = D; -} + A : Space, + S : Mapping<A>, + T : Mapping<A>, +{ } impl<F, S, T, A, B, X> GEMV<F, X, Pair<A, B>> for ColOp<S, T> where + X : Space, S : GEMV<F, X, A>, T : GEMV<F, X, B>, F : Num, Self : Linear<X, Codomain=Pair<A, B>> { - fn gemv(&self, y : &mut Pair<A, B>, α : F, x : &X, β : F) { - self.0.gemv(&mut y.0, α, x, β); + fn gemv<I : Instance<X>>(&self, y : &mut Pair<A, B>, α : F, x : I, β : F) { + self.0.gemv(&mut y.0, α, x.ref_instance(), β); self.1.gemv(&mut y.1, α, x, β); } - fn apply_mut(&self, y : &mut Pair<A, B>, x : &X){ - self.0.apply_mut(&mut y.0, x); + fn apply_mut<I : Instance<X>>(&self, y : &mut Pair<A, B>, x : I){ + self.0.apply_mut(&mut y.0, x.ref_instance()); self.1.apply_mut(&mut y.1, x); } /// Computes `y += Ax`, where `A` is `Self` - fn apply_add(&self, y : &mut Pair<A, B>, x : &X){ - self.0.apply_add(&mut y.0, x); + fn apply_add<I : Instance<X>>(&self, y : &mut Pair<A, B>, x : I){ + self.0.apply_add(&mut y.0, x.ref_instance()); self.1.apply_add(&mut y.1, x); } } -impl<A, B, Yʹ, R, S, T> Adjointable<Pair<A,B>,Yʹ> for RowOp<S, T> +impl<A, B, Yʹ, S, T> Adjointable<Pair<A,B>, Yʹ> for RowOp<S, T> where + A : Space, + B : Space, + Yʹ : Space, S : Adjointable<A, Yʹ>, T : Adjointable<B, Yʹ>, Self : Linear<Pair<A, B>>, - for<'a> ColOp<S::Adjoint<'a>, T::Adjoint<'a>> : Linear<Yʹ, Codomain=R>, + // for<'a> ColOp<S::Adjoint<'a>, T::Adjoint<'a>> : Linear< + // Yʹ, + // Codomain=Pair<S::AdjointCodomain, T::AdjointCodomain> + // >, { - type AdjointCodomain = R; + type AdjointCodomain = Pair<S::AdjointCodomain, T::AdjointCodomain>; type Adjoint<'a> = ColOp<S::Adjoint<'a>, T::Adjoint<'a>> where Self : 'a; fn adjoint(&self) -> Self::Adjoint<'_> { @@ -279,14 +306,21 @@ } } -impl<A, B, Yʹ, R, S, T> Preadjointable<Pair<A,B>,Yʹ> for RowOp<S, T> +impl<A, B, Yʹ, S, T> Preadjointable<Pair<A,B>, Yʹ> for RowOp<S, T> where + A : Space, + B : Space, + Yʹ : Space, S : Preadjointable<A, Yʹ>, T : Preadjointable<B, Yʹ>, Self : Linear<Pair<A, B>>, - for<'a> ColOp<S::Preadjoint<'a>, T::Preadjoint<'a>> : Adjointable<Yʹ, Pair<A,B>, Codomain=R>, + for<'a> ColOp<S::Preadjoint<'a>, T::Preadjoint<'a>> : Adjointable< + Yʹ, Pair<A,B>, + Codomain=Pair<S::PreadjointCodomain, T::PreadjointCodomain>, + AdjointCodomain = Self::Codomain, + >, { - type PreadjointCodomain = R; + type PreadjointCodomain = Pair<S::PreadjointCodomain, T::PreadjointCodomain>; type Preadjoint<'a> = ColOp<S::Preadjoint<'a>, T::Preadjoint<'a>> where Self : 'a; fn preadjoint(&self) -> Self::Preadjoint<'_> { @@ -297,10 +331,17 @@ impl<A, Xʹ, Yʹ, R, S, T> Adjointable<A,Pair<Xʹ,Yʹ>> for ColOp<S, T> where - S : Adjointable<A, Xʹ>, - T : Adjointable<A, Yʹ>, + A : Space, + Xʹ : Space, + Yʹ : Space, + R : Space + ClosedAdd, + S : Adjointable<A, Xʹ, AdjointCodomain = R>, + T : Adjointable<A, Yʹ, AdjointCodomain = R>, Self : Linear<A>, - for<'a> RowOp<S::Adjoint<'a>, T::Adjoint<'a>> : Linear<Pair<Xʹ,Yʹ>, Codomain=R>, + // for<'a> RowOp<S::Adjoint<'a>, T::Adjoint<'a>> : Linear< + // Pair<Xʹ,Yʹ>, + // Codomain=R, + // >, { type AdjointCodomain = R; type Adjoint<'a> = RowOp<S::Adjoint<'a>, T::Adjoint<'a>> where Self : 'a; @@ -312,10 +353,18 @@ impl<A, Xʹ, Yʹ, R, S, T> Preadjointable<A,Pair<Xʹ,Yʹ>> for ColOp<S, T> where - S : Preadjointable<A, Xʹ>, - T : Preadjointable<A, Yʹ>, + A : Space, + Xʹ : Space, + Yʹ : Space, + R : Space + ClosedAdd, + S : Preadjointable<A, Xʹ, PreadjointCodomain = R>, + T : Preadjointable<A, Yʹ, PreadjointCodomain = R>, Self : Linear<A>, - for<'a> RowOp<S::Preadjoint<'a>, T::Preadjoint<'a>> : Adjointable<Pair<Xʹ,Yʹ>, A, Codomain=R>, + for<'a> RowOp<S::Preadjoint<'a>, T::Preadjoint<'a>> : Adjointable< + Pair<Xʹ,Yʹ>, A, + Codomain = R, + AdjointCodomain = Self::Codomain, + >, { type PreadjointCodomain = R; type Preadjoint<'a> = RowOp<S::Preadjoint<'a>, T::Preadjoint<'a>> where Self : 'a; @@ -328,67 +377,73 @@ /// Diagonal operator pub struct DiagOp<S, T>(pub S, pub T); -impl<A, B, S, T> Apply<Pair<A, B>> for DiagOp<S, T> +impl<A, B, S, T> Mapping<Pair<A, B>> for DiagOp<S, T> where - S : Apply<A>, - T : Apply<B>, + A : Space, + B : Space, + S : Mapping<A>, + T : Mapping<B>, { - type Output = Pair<S::Output, T::Output>; + type Codomain = Pair<S::Codomain, T::Codomain>; - fn apply(&self, Pair(a, b) : Pair<A, B>) -> Self::Output { - Pair(self.0.apply(a), self.1.apply(b)) - } -} - -impl<'a, A, B, S, T> Apply<&'a Pair<A, B>> for DiagOp<S, T> -where - S : Apply<&'a A>, - T : Apply<&'a B>, -{ - type Output = Pair<S::Output, T::Output>; - - fn apply(&self, Pair(ref a, ref b) : &'a Pair<A, B>) -> Self::Output { + fn apply<I : Instance<Pair<A, B>>>(&self, x : I) -> Self::Codomain { + let Pair(a, b) = x.decompose(); Pair(self.0.apply(a), self.1.apply(b)) } } -impl<A, B, S, T, D> Linear<Pair<A, B>> for DiagOp<S, T> +impl<A, B, S, T> Linear<Pair<A, B>> for DiagOp<S, T> where - DiagOp<S, T> : Apply<Pair<A, B>, Output=D> + for<'a> Apply<&'a Pair<A, B>, Output=D>, -{ - type Codomain = D; -} + A : Space, + B : Space, + S : Linear<A>, + T : Linear<B>, +{ } impl<F, S, T, A, B, U, V> GEMV<F, Pair<U, V>, Pair<A, B>> for DiagOp<S, T> where + A : Space, + B : Space, + U : Space, + V : Space, S : GEMV<F, U, A>, T : GEMV<F, V, B>, F : Num, - Self : Linear<Pair<U, V>, Codomain=Pair<A, B>> + Self : Linear<Pair<U, V>, Codomain=Pair<A, B>>, { - fn gemv(&self, y : &mut Pair<A, B>, α : F, x : &Pair<U, V>, β : F) { - self.0.gemv(&mut y.0, α, &x.0, β); - self.1.gemv(&mut y.1, α, &x.1, β); + fn gemv<I : Instance<Pair<U, V>>>(&self, y : &mut Pair<A, B>, α : F, x : I, β : F) { + let Pair(u, v) = x.decompose(); + self.0.gemv(&mut y.0, α, u, β); + self.1.gemv(&mut y.1, α, v, β); } - fn apply_mut(&self, y : &mut Pair<A, B>, x : &Pair<U, V>){ - self.0.apply_mut(&mut y.0, &x.0); - self.1.apply_mut(&mut y.1, &x.1); + fn apply_mut<I : Instance<Pair<U, V>>>(&self, y : &mut Pair<A, B>, x : I){ + let Pair(u, v) = x.decompose(); + self.0.apply_mut(&mut y.0, u); + self.1.apply_mut(&mut y.1, v); } /// Computes `y += Ax`, where `A` is `Self` - fn apply_add(&self, y : &mut Pair<A, B>, x : &Pair<U, V>){ - self.0.apply_add(&mut y.0, &x.0); - self.1.apply_add(&mut y.1, &x.1); + fn apply_add<I : Instance<Pair<U, V>>>(&self, y : &mut Pair<A, B>, x : I){ + let Pair(u, v) = x.decompose(); + self.0.apply_add(&mut y.0, u); + self.1.apply_add(&mut y.1, v); } } -impl<A, B, Xʹ, Yʹ, R, S, T> Adjointable<Pair<A,B>,Pair<Xʹ,Yʹ>> for DiagOp<S, T> +impl<A, B, Xʹ, Yʹ, R, S, T> Adjointable<Pair<A,B>, Pair<Xʹ,Yʹ>> for DiagOp<S, T> where + A : Space, + B : Space, + Xʹ: Space, + Yʹ : Space, + R : Space, S : Adjointable<A, Xʹ>, T : Adjointable<B, Yʹ>, Self : Linear<Pair<A, B>>, - for<'a> DiagOp<S::Adjoint<'a>, T::Adjoint<'a>> : Linear<Pair<Xʹ,Yʹ>, Codomain=R>, + for<'a> DiagOp<S::Adjoint<'a>, T::Adjoint<'a>> : Linear< + Pair<Xʹ,Yʹ>, Codomain=R, + >, { type AdjointCodomain = R; type Adjoint<'a> = DiagOp<S::Adjoint<'a>, T::Adjoint<'a>> where Self : 'a; @@ -398,12 +453,21 @@ } } -impl<A, B, Xʹ, Yʹ, R, S, T> Preadjointable<Pair<A,B>,Pair<Xʹ,Yʹ>> for DiagOp<S, T> +impl<A, B, Xʹ, Yʹ, R, S, T> Preadjointable<Pair<A,B>, Pair<Xʹ,Yʹ>> for DiagOp<S, T> where + A : Space, + B : Space, + Xʹ: Space, + Yʹ : Space, + R : Space, S : Preadjointable<A, Xʹ>, T : Preadjointable<B, Yʹ>, Self : Linear<Pair<A, B>>, - for<'a> DiagOp<S::Preadjoint<'a>, T::Preadjoint<'a>> : Adjointable<Pair<Xʹ,Yʹ>, Pair<A, B>, Codomain=R>, + for<'a> DiagOp<S::Preadjoint<'a>, T::Preadjoint<'a>> : Adjointable< + Pair<Xʹ,Yʹ>, Pair<A, B>, + Codomain=R, + AdjointCodomain = Self::Codomain, + >, { type PreadjointCodomain = R; type Preadjoint<'a> = DiagOp<S::Preadjoint<'a>, T::Preadjoint<'a>> where Self : 'a; @@ -416,3 +480,65 @@ /// Block operator pub type BlockOp<S11, S12, S21, S22> = ColOp<RowOp<S11, S12>, RowOp<S21, S22>>; + +macro_rules! pairnorm { + ($expj:ty) => { + impl<F, A, B, S, T, ExpA, ExpB, ExpR> + BoundedLinear<Pair<A, B>, PairNorm<ExpA, ExpB, $expj>, ExpR, F> + for RowOp<S, T> + where + F : Float, + A : Space, + B : Space, + S : BoundedLinear<A, ExpA, ExpR, F>, + T : BoundedLinear<B, ExpB, ExpR, F>, + S::Codomain : Add<T::Codomain>, + <S::Codomain as Add<T::Codomain>>::Output : Space, + ExpA : NormExponent, + ExpB : NormExponent, + ExpR : NormExponent, + { + fn opnorm_bound( + &self, + PairNorm(expa, expb, _) : PairNorm<ExpA, ExpB, $expj>, + expr : ExpR + ) -> F { + // An application of the triangle inequality bounds the norm by the maximum + // of the individual norms. A simple observation shows this to be exact. + let na = self.0.opnorm_bound(expa, expr); + let nb = self.1.opnorm_bound(expb, expr); + na.max(nb) + } + } + + impl<F, A, S, T, ExpA, ExpS, ExpT> + BoundedLinear<A, ExpA, PairNorm<ExpS, ExpT, $expj>, F> + for ColOp<S, T> + where + F : Float, + A : Space, + S : BoundedLinear<A, ExpA, ExpS, F>, + T : BoundedLinear<A, ExpA, ExpT, F>, + ExpA : NormExponent, + ExpS : NormExponent, + ExpT : NormExponent, + { + fn opnorm_bound( + &self, + expa : ExpA, + PairNorm(exps, expt, _) : PairNorm<ExpS, ExpT, $expj> + ) -> F { + // This is based on the rule for RowOp and ‖A^*‖ = ‖A‖, hence, + // for A=[S; T], ‖A‖=‖[S^*, T^*]‖ ≤ max{‖S^*‖, ‖T^*‖} = max{‖S‖, ‖T‖} + let ns = self.0.opnorm_bound(expa, exps); + let nt = self.1.opnorm_bound(expa, expt); + ns.max(nt) + } + } + } +} + +pairnorm!(L1); +pairnorm!(L2); +pairnorm!(Linfinity); +