Updated operators to print with hat

CHANGELOG.md

@@ -1,5 +1,9 @@
 # News
 
+## v0.4.6 - dev
+
+- Operators now print with a hat
+
 ## v0.4.5 - 2024-11-14
 
 - Updated compat lower bounds for Symbolics to v6 (and for SymbolicUtils and TermInterface)

docs/src/introduction.md

@@ -31,7 +31,7 @@ julia> @ket k # object of type SKet
 |k⟩
 
 julia> @op A # object of type SOperator
-A
+Â
 
 julia> @superop S # object of type SSuperOperator
 S
@@ -41,13 +41,13 @@ By default, each of the above macros defines a symbolic quantum object in the sp
 
 ```jldoctest
 julia> @op B FockBasis(Inf, 0.0)
-B
+B̂
 
 julia> basis(B)
 Fock(cutoff=Inf)
 
 julia> @op C SpinBasis(1//2)⊗SpinBasis(5//2)
-C
+Ĉ
 
 julia> basis(C)
 [Spin(1/2) ⊗ Spin(5/2)]
@@ -69,7 +69,7 @@ julia> 2*k
 2|k⟩
 
 julia> A*k
-A|k⟩
+Â|k⟩
 ```
 
 Similar scaling procedures can be performed on bras and operators. Addition between symbolic objects is also available, for instance:
@@ -78,7 +78,7 @@ Similar scaling procedures can be performed on bras and operators. Addition betw
 julia> @op A₁; @op A₂;
 
 julia> A₁+A₂
-(A₁+A₂)
+(Â₁+Â₂)
 
 julia> @bra b;
 
@@ -117,10 +117,10 @@ More involved combinations of operations can be explored. Here are few other str
 julia> @bra b; @ket k; @op A; @op B;
 
 julia> 3*A*B*k
-3AB|k⟩
+3ÂB̂|k⟩
 
 julia> A⊗(k*b + B)
-(A⊗(B+|k⟩⟨b|))
+(Â⊗(B̂+|k⟩⟨b|))
 
 julia> A-A
 𝟎
@@ -135,10 +135,10 @@ QuantumSymbolics supports a wide variety of linear algebra on symbolic bras, ket
 julia> @op A; @op B;
 
 julia> commutator(A, B)
-[A,B]
+[Â,B̂]
 
 julia> anticommutator(A, B)
-{A,B}
+{Â,B̂}
 
 julia> commutator(A, A)
 𝟎
@@ -149,13 +149,13 @@ Or, one can take the dagger of a quantum object with the [`dagger`](@ref) functi
 julia> @ket k; @op A; @op B;
 
 julia> dagger(A)
-A†
+†
 
 julia> dagger(A*k)
-|k⟩†A†
+|k⟩†Â†
 
 julia> dagger(A*B)
-B†A†
+B̂†Â†
 ```
 Below, we state all of the supported linear algebra operations on quantum objects:
 
@@ -259,18 +259,18 @@ Symbolic expressions containing quantum objects can be expanded with the [`qexpa
 julia> @op A; @op B; @op C;
 
 julia> qexpand(A⊗(B+C))
-((A⊗B)+(A⊗C))
+((Â⊗B̂)+(Â⊗Ĉ))
 
 julia> qexpand((B+C)*A)
-(BA+CA)
+(B̂Â+ĈÂ)
 
 julia> @ket k₁; @ket k₂; @ket k₃;
 
 julia> qexpand(k₁⊗(k₂+k₃))
 (|k₁⟩|k₂⟩+|k₁⟩|k₃⟩)
 
 julia> qexpand((A*B)*(k₁+k₂))
-(AB|k₁⟩+AB|k₂⟩)
+(ÂB̂|k₁⟩+ÂB̂|k₂⟩)
 ```
 
 ## Numerical Translation of Symbolic Objects

src/QSymbolicsBase/basic_ops_homogeneous.jl

@@ -13,10 +13,10 @@ julia> 2*k
 2|k⟩
 
 julia> @op A
-A
+Â
 
 julia> 2*A
-2A
+2Â
 ```
 """
 @withmetadata struct SScaled{T<:QObj} <: Symbolic{T}
@@ -125,7 +125,7 @@ end
 julia> @op A; @op B;
 
 julia> A*B
-AB
+ÂB̂
 ```
 """
 @withmetadata struct SMulOperator <: Symbolic{AbstractOperator}
@@ -165,7 +165,7 @@ julia> k₁ ⊗ k₂
 julia> @op A; @op B;
 
 julia> A ⊗ B
-(A⊗B)
+(Â⊗B̂)
 ```
 """
 @withmetadata struct STensor{T<:QObj} <: Symbolic{T}

src/QSymbolicsBase/basic_ops_inhomogeneous.jl

@@ -8,7 +8,7 @@
 julia> @ket k; @op A;
 
 julia> A*k
-A|k⟩
+Â|k⟩
 ```
 """
 @withmetadata struct SApplyKet <: Symbolic{AbstractKet}
@@ -41,7 +41,7 @@ basis(x::SApplyKet) = basis(x.ket)
 julia> @bra b; @op A;
 
 julia> b*A
-⟨b|A
+⟨b|Â
 ```
 """
 @withmetadata struct SApplyBra <: Symbolic{AbstractBra}

src/QSymbolicsBase/basic_superops.jl

@@ -13,7 +13,7 @@ julia> K = kraus(A₁, A₂, A₃)
 julia> @op ρ;
 
 julia> K*ρ
-(A₁ρA₁†+A₂ρA₂†+A₃ρA₃†)
+(Â₁ρ̂Â₁†+Â₂ρ̂Â₂†+Â₃ρ̂Â₃†)
 ```
 """
 @withmetadata struct KrausRepr <: Symbolic{AbstractSuperOperator}
@@ -41,7 +41,7 @@ Base.show(io::IO, x::KrausRepr) = print(io, "𝒦("*join([symbollabel(i) for i i
 julia> @op A; @superop S;
 
 julia> S*A
-S[A]
+S[Â]
 ```
 """
 @withmetadata struct SSuperOpApply <: Symbolic{AbstractOperator}

src/QSymbolicsBase/linalg.jl

@@ -14,7 +14,7 @@ function anticommutator end
 julia> @op A; @op B;
 
 julia> commutator(A, B)
-[A,B]
+[Â,B̂]
 
 julia> commutator(A, A)
 𝟎
@@ -51,7 +51,7 @@ basis(x::SCommutator) = basis(x.op1)
 julia> @op A; @op B;
 
 julia> anticommutator(A, B)
-{A,B}
+{Â,B̂}
 ```
 """
 @withmetadata struct SAnticommutator <: Symbolic{AbstractOperator}
@@ -85,7 +85,7 @@ basis(x::SAnticommutator) = basis(x.op1)
 julia> @op A; @ket k;
 
 julia> conj(A)
-Aˣ
+Âˣ
 
 julia> conj(k)
 |k⟩ˣ
@@ -161,10 +161,10 @@ end
 julia> @op A; @op B; @ket k;
 
 julia> transpose(A)
-Aᵀ
+Âᵀ
 
 julia> transpose(A+B)
-(Aᵀ+Bᵀ)
+(Âᵀ+B̂ᵀ)
 
 julia> transpose(k)
 |k⟩ᵀ
@@ -206,20 +206,20 @@ end
 julia> @ket a; @op A;
 
 julia> dagger(2*im*A*a)
-(0 - 2im)|a⟩†A†
+(0 - 2im)|a⟩†Â†
 
 julia> @op B;
 
 julia> dagger(A*B)
-B†A†
+B̂†Â†
 
 julia> ℋ = SHermitianOperator(:ℋ); U = SUnitaryOperator(:U);
 
 julia> dagger(ℋ)
-ℋ
+ℋ̂
 
 julia> dagger(U)
-U⁻¹
+Û⁻¹
 ```
 """
 @withmetadata struct SDagger{T<:QObj} <: Symbolic{T}
@@ -275,7 +275,7 @@ end
 julia> @op A; @op B;
 
 julia> tr(A)
-tr(A)
+tr(Â)
 
 julia> tr(commutator(A, B))
 0
@@ -318,35 +318,35 @@ Base.isequal(x::STrace, y::STrace) = isequal(x.op, y.op)
 julia> @op 𝒪 SpinBasis(1//2)⊗SpinBasis(1//2);
 
 julia> op = ptrace(𝒪, 1)
-tr1(𝒪)
+tr1(𝒪̂)
 
 julia> QuantumSymbolics.basis(op)
 Spin(1/2)
 
 julia> @op A; @op B;
 
 julia> ptrace(A⊗B, 1)
-(tr(A))B
+(tr(Â))B̂
 
 julia> @ket k; @bra b;
 
 julia> factorizable = A ⊗ (k*b)
-(A⊗|k⟩⟨b|)
+(Â⊗|k⟩⟨b|)
 
 julia> ptrace(factorizable, 1)
-(tr(A))|k⟩⟨b|
+(tr(Â))|k⟩⟨b|
 
 julia> ptrace(factorizable, 2)
-(⟨b||k⟩)A
+(⟨b||k⟩)Â
 
 julia> mixed_state = (A⊗(k*b)) + ((k*b)⊗B)
-((A⊗|k⟩⟨b|)+(|k⟩⟨b|⊗B))
+((Â⊗|k⟩⟨b|)+(|k⟩⟨b|⊗B̂))
 
 julia> ptrace(mixed_state, 1)
-((0 + ⟨b||k⟩)B+(tr(A))|k⟩⟨b|)
+((0 + ⟨b||k⟩)B̂+(tr(Â))|k⟩⟨b|)
 
 julia> ptrace(mixed_state, 2)
-((0 + ⟨b||k⟩)A+(tr(B))|k⟩⟨b|)
+((0 + ⟨b||k⟩)Â+(tr(B̂))|k⟩⟨b|)
 ```
 """
 @withmetadata struct SPartialTrace <: Symbolic{AbstractOperator}
@@ -441,7 +441,7 @@ end
 julia> @op A;
 
 julia> inv(A)
-A⁻¹
+Â⁻¹
 
 julia> inv(A)*A
 𝕀
@@ -474,7 +474,7 @@ inv(x::Symbolic{AbstractOperator}) = SInvOperator(x)
 julia> @op A; @op B;
 
 julia> exp(A)
-exp(A)
+exp(Â)
 ```
 """
 @withmetadata struct SExpOperator <: Symbolic{AbstractOperator}
@@ -502,10 +502,10 @@ exp(x::Symbolic{AbstractOperator}) = SExpOperator(x)
 julia> @op A; @op B;
 
 julia> vec(A)
-|A⟩⟩
+|Â⟩⟩
 
 julia> vec(A+B)
-(|A⟩⟩+|B⟩⟩)
+(|Â⟩⟩+|B̂⟩⟩)
 ```
 """
 @withmetadata struct SVec <: Symbolic{AbstractKet}

src/QSymbolicsBase/literal_objects.jl

@@ -70,10 +70,10 @@ Define a symbolic ket of type `SOperator`. By default, the defined basis is the
 
 ```jldoctest
 julia> @op A
-A
+Â
 
 julia> @op B FockBasis(2)
-B
+B̂
 ```
 """
 macro op(name, basis)
@@ -138,7 +138,10 @@ basis(x::SymQ) = x.basis
 
 Base.show(io::IO, x::SKet) = print(io, "|$(symbollabel(x))⟩")
 Base.show(io::IO, x::SBra) = print(io, "⟨$(symbollabel(x))|")
-Base.show(io::IO, x::Union{SOperator,SHermitianOperator,SUnitaryOperator,SHermitianUnitaryOperator,SSuperOperator}) = print(io, "$(symbollabel(x))")
+Base.show(io::IO, x::Union{SOperator,SHermitianOperator,SUnitaryOperator,SHermitianUnitaryOperator}) = begin
+    symbol_name = String(symbollabel(x))
+    print(io, symbol_name[1:1] * "\u0302" * symbol_name[2:end]) # add hat to the first character
+end
 Base.show(io::IO, x::SymQObj) = print(io, symbollabel(x)) # fallback that probably is not great
 
 struct SZero{T<:QObj} <: Symbolic{T} end

src/QSymbolicsBase/rules.jl

@@ -182,15 +182,15 @@ Manually expand a symbolic expression of quantum objects.
 julia> @op A; @op B; @op C;
 
 julia> qexpand(commutator(A, B))
-(-1BA+AB)
+(-1B̂Â+ÂB̂)
 
 julia> qexpand(A⊗(B+C))
-((A⊗B)+(A⊗C))
+((Â⊗B̂)+(Â⊗Ĉ))
 
 julia> @ket k₁; @ket k₂;
 
 julia> qexpand(A*(k₁+k₂))
-(A|k₁⟩+A|k₂⟩)
+(Â|k₁⟩+Â|k₂⟩)
 ```
 """
 function qexpand(s)