Merge pull request #103 from bsc-quantic/refactor/oop

Refactor `TensorNetwork` to class-based OOP organization

Project.toml

@@ -4,7 +4,7 @@ authors = ["Sergio Sánchez Ramírez <[email protected]>"]
 version = "0.2.0"
 
 [deps]
-Bijections = "e2ed5e7c-b2de-5872-ae92-c73ca462fb04"
+Classes = "1a9c1350-211b-5766-99cd-4544d885a0d1"
 Combinatorics = "861a8166-3701-5b0c-9a16-15d98fcdc6aa"
 DeltaArrays = "10b0fc19-5ccc-4427-889b-d75dd6306188"
 EinExprs = "b1794770-133b-4de1-afb4-526377e9f4c5"
@@ -34,7 +34,6 @@ TenetMakieExt = "Makie"
 TenetQuacExt = "Quac"
 
 [compat]
-Bijections = "0.1"
 ChainRulesCore = "1.0"
 Combinatorics = "1.0"
 DeltaArrays = "0.1.1"

docs/src/contraction.md

@@ -3,7 +3,7 @@
 Contraction path optimization and execution is delegated to the [`EinExprs`](https://github.com/bsc-quantic/EinExprs) library. A `EinExpr` is a lower-level form of a Tensor Network, in which the contraction path has been laid out as a tree. It is similar to a symbolic expression (i.e. `Expr`) but in which every node represents an Einstein summation expression (aka `einsum`).
 
 ```@docs
-einexpr(::TensorNetwork)
-contract(::TensorNetwork)
+einexpr(::Tenet.AbstractTensorNetwork)
+contract(::Tenet.AbstractTensorNetwork)
 contract!
 ```

docs/src/examples/ad-tn.md

@@ -19,7 +19,7 @@ rng = seed!(4) # hide
 ψ = rand(rng, MPS{Open}, n = 4, p = 2, χ = 2) # hide
 ϕ = rand(rng, MPS{Open}, n = 4, p = 2, χ = 4) # hide
 
-tn = hcat(ψ, ϕ)
+tn = merge(ψ, ϕ')
 
 plot(tn) # hide
 ```

docs/src/examples/google-rqc.md

@@ -42,7 +42,7 @@ _sites = [5, 6, 14, 15, 16, 17, 24, 25, 26, 27, 28, 32, 33, 34, 35, 36, 37, 38,
 
 # load circuit and convert to `TensorNetwork`
 circuit = QuacIO.parse(joinpath(@__DIR__, "sycamore_53_10_0.qasm"), format = QuacIO.Qflex(), sites = _sites);
-tn = TensorNetwork(circuit)
+tn = QuantumTensorNetwork(circuit)
 tn = view(tn, [i => 1 for i in inds(tn, set=:open)]...)
 plot(tn) # hide
 ```

docs/src/quantum/index.md

@@ -1,44 +1,30 @@
 # Introduction
 
-In `Tenet`, we define a [`Quantum`](@ref) Tensor Network as a [`TensorNetwork`](@ref) with a notion of sites and directionality.
-
-```@docs
-Quantum
-```
+In `Tenet`, we define a [`QuantumTensorNetwork`](@ref) as a [`TensorNetwork`](@ref) with a notion of sites and directionality.
 
 ```@docs
+QuantumTensorNetwork
 plug
-```
-
-```@docs
 sites
 ```
 
-```@docs
-tensors(::TensorNetwork{<:Quantum}, ::Integer)
-```
-
-```@docs
-boundary
-```
-
 ## Adjoint
 
 ```@docs
 adjoint
 ```
 
-## Concatenation
+## Norm
 
 ```@docs
-hcat(::TensorNetwork{<:Quantum}, ::TensorNetwork{<:Quantum})
+LinearAlgebra.norm(::Tenet.AbstractQuantumTensorNetwork, ::Real)
+LinearAlgebra.normalize!(::Tenet.AbstractQuantumTensorNetwork, ::Real)
 ```
 
-## Norm
+## Trace
 
 ```@docs
-LinearAlgebra.norm(::TensorNetwork{<:Quantum}, p::Real)
-LinearAlgebra.normalize!(::TensorNetwork{<:Quantum}, ::Real)
+LinearAlgebra.tr(::Tenet.AbstractQuantumTensorNetwork)
 ```
 
 ## Fidelity

docs/src/tensor-network.md

@@ -28,28 +28,26 @@ Information about a `TensorNetwork` can be queried with the following functions.
 ## Query information
 
 ```@docs
-inds(::TensorNetwork)
-size(::TensorNetwork)
-tensors(::TensorNetwork)
-length(::TensorNetwork)
-ansatz
+inds(::Tenet.AbstractTensorNetwork)
+size(::Tenet.AbstractTensorNetwork)
+tensors(::Tenet.AbstractTensorNetwork)
 ```
 
 ## Modification
 
 ### Add/Remove tensors
 
 ```@docs
-push!(::TensorNetwork, ::Tensor)
-append!(::TensorNetwork, ::Base.AbstractVecOrTuple{<:Tensor})
-pop!(::TensorNetwork, ::Tensor)
-delete!(::TensorNetwork, ::Any)
+push!(::Tenet.AbstractTensorNetwork, ::Tensor)
+append!(::Tenet.AbstractTensorNetwork, ::Base.AbstractVecOrTuple{<:Tensor})
+merge!(::Tenet.AbstractTensorNetwork, ::Tenet.AbstractTensorNetwork)
+pop!(::Tenet.AbstractTensorNetwork, ::Tensor)
+delete!(::Tenet.AbstractTensorNetwork, ::Any)
 ```
 
 ### Replace existing elements
 
 ```@docs
-replace
 replace!
 ```
 
@@ -59,12 +57,12 @@ replace!
 select
 selectdim
 slice!
-view(::TensorNetwork)
+view(::Tenet.AbstractTensorNetwork)
 ```
 
 ## Miscelaneous
 
 ```@docs
-Base.copy(::TensorNetwork)
+Base.copy(::Tenet.AbstractTensorNetwork)
 Base.rand(::Type{TensorNetwork}, n::Integer, regularity::Integer)
 ```

docs/src/transformations.md

@@ -294,7 +294,7 @@ set_theme!(resolution=(800,400)) # hide
 
 sites = [5, 6, 14, 15, 16, 17, 24, 25, 26, 27, 28, 32, 33, 34, 35, 36, 37, 38, 39, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 61, 62, 63, 64, 65, 66, 67, 72, 73, 74, 75, 76, 83, 84, 85, 94]
 circuit = QuacIO.parse(joinpath(@__DIR__, "sycamore_53_10_0.qasm"), format=QuacIO.Qflex(), sites=sites)
-tn = TensorNetwork(circuit)
+tn = QuantumTensorNetwork(circuit)
 
 # Apply transformations to the tensor network
 transformed_tn = transform(tn, [Tenet.AntiDiagonalGauging, Tenet.DiagonalReduction, Tenet.ColumnReduction, Tenet.RankSimplification])

ext/TenetChainRulesCoreExt.jl

@@ -1,6 +1,7 @@
 module TenetChainRulesCoreExt
 
 using Tenet
+using Classes
 using ChainRulesCore
 
 function ChainRulesCore.ProjectTo(tensor::T) where {T<:Tensor}
@@ -26,29 +27,45 @@ ChainRulesCore.rrule(T::Type{<:Tensor}, data, inds) = T(data, inds), Tensor_pull
 @non_differentiable intersect(s::Base.AbstractVecOrTuple{Symbol}, itrs::Base.AbstractVecOrTuple{Symbol}...)
 @non_differentiable symdiff(s::Base.AbstractVecOrTuple{Symbol}, itrs::Base.AbstractVecOrTuple{Symbol}...)
 
-function ChainRulesCore.ProjectTo(tn::T) where {T<:TensorNetwork}
-    ProjectTo{T}(; tensors = ProjectTo(tn.tensors), metadata = tn.metadata)
+function ChainRulesCore.ProjectTo(tn::T) where {T<:absclass(TensorNetwork)}
+    # TODO create function to extract extra fields
+    fields = map(fieldnames(T)) do fieldname
+        if fieldname === :tensors
+            :tensors => ProjectTo(tn.tensors)
+        else
+            fieldname => getfield(tn, fieldname)
+        end
+    end
+    ProjectTo{T}(; fields...)
 end
 
-function (projector::ProjectTo{T})(dx::Union{T,Tangent{T}}) where {T<:TensorNetwork}
+function (projector::ProjectTo{T})(dx::Union{T,Tangent{T}}) where {T<:absclass(TensorNetwork)}
     dx.tensors isa NoTangent && return NoTangent()
     Tangent{TensorNetwork}(tensors = projector.tensors(dx.tensors))
 end
 
-function Base.:+(x::TensorNetwork{A}, Δ::Tangent{TensorNetwork}) where {A<:Ansatz}
+function Base.:+(x::T, Δ::Tangent{TensorNetwork}) where {T<:absclass(TensorNetwork)}
     # TODO match tensors by indices
-    tensors = map(+, x.tensors, Δ.tensors)
-    TensorNetwork{A}(tensors; x.metadata...)
+    tensors = map(+, tensors(x), Δ.tensors)
+
+    # TODO create function fitted for this? or maybe standardize constructors?
+    T(map(fieldnames(T)) do fieldname
+        if fieldname === :tensors
+            tensors
+        else
+            getfield(x, fieldname)
+        end
+    end...)
 end
 
-function ChainRulesCore.frule((_, Δ), T::Type{<:TensorNetwork}, tensors; metadata...)
-    T(tensors; metadata...), Tangent{TensorNetwork}(tensors = Δ)
+function ChainRulesCore.frule((_, Δ), T::Type{<:absclass(TensorNetwork)}, tensors)
+    T(tensors), Tangent{TensorNetwork}(tensors = Δ)
 end
 
 TensorNetwork_pullback(Δ::Tangent{TensorNetwork}) = (NoTangent(), Δ.tensors)
 TensorNetwork_pullback(Δ::AbstractThunk) = TensorNetwork_pullback(unthunk(Δ))
-function ChainRulesCore.rrule(T::Type{<:TensorNetwork}, tensors; metadata...)
-    T(tensors; metadata...), TensorNetwork_pullback
+function ChainRulesCore.rrule(T::Type{<:absclass(TensorNetwork)}, tensors)
+    T(tensors), TensorNetwork_pullback
 end
 
 end

ext/TenetChainRulesTestUtilsExt.jl

@@ -4,11 +4,10 @@ using Tenet
 using ChainRulesCore
 using ChainRulesTestUtils
 using Random
+using Classes
 
-function ChainRulesTestUtils.rand_tangent(rng::AbstractRNG, x::TensorNetwork)
-    return Tangent{TensorNetwork}(
-        tensors = Tensor[ProjectTo(tensor)(rand_tangent.(Ref(rng), tensor)) for tensor in tensors(x)],
-    )
+function ChainRulesTestUtils.rand_tangent(rng::AbstractRNG, x::T) where {T<:absclass(TensorNetwork)}
+    return Tangent{T}(tensors = [ProjectTo(tensor)(rand_tangent.(Ref(rng), tensor)) for tensor in tensors(x)])
 end
 
 end

ext/TenetFiniteDifferencesExt.jl

@@ -1,13 +1,22 @@
 module TenetFiniteDifferencesExt
 
 using Tenet
+using Classes
 using FiniteDifferences
 
-function FiniteDifferences.to_vec(x::TensorNetwork{A}) where {A<:Ansatz}
+function FiniteDifferences.to_vec(x::T) where {T<:absclass(TensorNetwork)}
     x_vec, back = to_vec(x.tensors)
     function TensorNetwork_from_vec(v)
         tensors = back(v)
-        TensorNetwork{A}(tensors; x.metadata...)
+
+        # TODO create function fitted for this? or maybe standardize constructors?
+        T(map(fieldnames(T)) do fieldname
+            if fieldname === :tensors
+                tensors
+            else
+                getfield(x, fieldname)
+            end
+        end...)
     end
 
     return x_vec, TensorNetwork_from_vec

ext/TenetMakieExt.jl

@@ -4,6 +4,7 @@ using Tenet
 using Combinatorics: combinations
 using Graphs
 using Makie
+using Classes
 
 using GraphMakie
 
@@ -19,7 +20,7 @@ Plot a [`TensorNetwork`](@ref) as a graph.
   - `labels` If `true`, show the labels of the tensor indices. Defaults to `false`.
   - The rest of `kwargs` are passed to `GraphMakie.graphplot`.
 """
-function Makie.plot(@nospecialize tn::TensorNetwork; kwargs...)
+function Makie.plot(@nospecialize tn::absclass(TensorNetwork); kwargs...)
     f = Figure()
     ax, p = plot!(f[1, 1], tn; kwargs...)
     return Makie.FigureAxisPlot(f, ax, p)
@@ -28,7 +29,7 @@ end
 # NOTE this is a hack! we did it in order not to depend on NetworkLayout but can be unstable
 __networklayout_dim(x) = typeof(x).super.parameters |> first
 
-function Makie.plot!(f::Union{Figure,GridPosition}, @nospecialize tn::TensorNetwork; kwargs...)
+function Makie.plot!(f::Union{Figure,GridPosition}, @nospecialize tn::absclass(TensorNetwork); kwargs...)
     ax = if haskey(kwargs, :layout) && __networklayout_dim(kwargs[:layout]) == 3
         Axis3(f[1, 1])
     else
@@ -45,7 +46,7 @@ function Makie.plot!(f::Union{Figure,GridPosition}, @nospecialize tn::TensorNetw
     return Makie.AxisPlot(ax, p)
 end
 
-function Makie.plot!(ax::Union{Axis,Axis3}, @nospecialize tn::TensorNetwork; labels = false, kwargs...)
+function Makie.plot!(ax::Union{Axis,Axis3}, @nospecialize tn::absclass(TensorNetwork); labels = false, kwargs...)
     hypermap = Tenet.hyperflatten(tn)
     tn = transform(tn, Tenet.HyperindConverter)
 

ext/TenetQuacExt.jl

@@ -2,12 +2,11 @@ module TenetQuacExt
 
 using Tenet
 using Quac: Circuit, lanes, arraytype, Swap
-using Bijections
 
-function Tenet.TensorNetwork(circuit::Circuit)
+function Tenet.QuantumTensorNetwork(circuit::Circuit)
     n = lanes(circuit)
     wire = [[Tenet.letter(i)] for i in 1:n]
-    tensors = Tensor[]
+    tn = TensorNetwork()
 
     i = n + 1
 
@@ -29,15 +28,13 @@ function Tenet.TensorNetwork(circuit::Circuit)
         end |> x -> zip(x...) |> Iterators.flatten |> collect
 
         tensor = Tensor(array, inds)
-        push!(tensors, tensor)
+        push!(tn, tensor)
     end
 
-    interlayer = [
-        Bijection(Dict([site => first(index) for (site, index) in enumerate(wire)])),
-        Bijection(Dict([site => last(index) for (site, index) in enumerate(wire)])),
-    ]
+    input = first.(wire)
+    output = last.(wire)
 
-    return TensorNetwork{Quantum}(tensors; plug = Tenet.Operator, interlayer)
+    return QuantumTensorNetwork(tn, input, output)
 end
 
 end

src/Helpers.jl

@@ -67,16 +67,6 @@ julia> letter(20204)
 letter(i) =
     Iterators.drop(Iterators.filter(isletter, Iterators.map(Char, 1:2^21-1)), i - 1) |> iterate |> first |> Symbol
 
-Base.merge(@nospecialize(A::Type{<:NamedTuple}), @nospecialize(Bs::Type{<:NamedTuple}...)) = NamedTuple{
-    foldl((acc, B) -> (acc..., B...), Iterators.map(fieldnames, Bs); init = fieldnames(A)),
-    foldl((acc, B) -> Tuple{fieldtypes(acc)...,B...}, Iterators.map(fieldtypes, Bs); init = A),
-}
-
-function superansatzes(T)
-    S = supertype(T)
-    return T === Ansatz ? (T,) : (T, superansatzes(S)...)
-end
-
 # NOTE from https://stackoverflow.com/q/54652787
 function nonunique(x)
     uniqueindexes = indexin(unique(x), x)

src/Numerics.jl

@@ -1,7 +1,6 @@
 using OMEinsum
 using LinearAlgebra
 using UUIDs: uuid4
-using EinExprs: inds
 
 # TODO test array container typevar on output
 for op in [
@@ -34,7 +33,7 @@ end
 __omeinsum_sym2str(x) = String[string(i) for i in x]
 
 """
-    contract(a::Tensor[, b::Tensor, dims=nonunique([inds(a)..., inds(b)...])])
+    contract(a::Tensor[, b::Tensor]; dims=nonunique([inds(a)..., inds(b)...]))
 
 Perform tensor contraction operation.
 """