Bump Version

Project.toml

@@ -1,17 +1,17 @@
-name = "ToQUBO"
-uuid = "9a412ddf-83fa-43b6-9748-7843c851aa65"
+name    = "ToQUBO"
+uuid    = "9a412ddf-83fa-43b6-9748-7843c851aa65"
 authors = ["pedromxavier <[email protected]>", "pedroripper <[email protected]>", "joaquimg <[email protected]>", "AndradeTiago <[email protected]>", "bernalde <[email protected]>"]
-version = "0.1.7"
+version = "0.1.8-dev"
 
 [deps]
-MathOptInterface = "b8f27783-ece8-5eb3-8dc8-9495eed66fee"
+MathOptInterface          = "b8f27783-ece8-5eb3-8dc8-9495eed66fee"
 PseudoBooleanOptimization = "c8fa9a04-bc42-452d-8558-dc51757be744"
-QUBOTools = "60eb5b62-0a39-4ddc-84c5-97d2adff9319"
-Random = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
-TOML = "fa267f1f-6049-4f14-aa54-33bafae1ed76"
+QUBOTools                 = "60eb5b62-0a39-4ddc-84c5-97d2adff9319"
+Random                    = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
+TOML                      = "fa267f1f-6049-4f14-aa54-33bafae1ed76"
 
 [compat]
-MathOptInterface = "1"
+MathOptInterface          = "1"
 PseudoBooleanOptimization = "0.2"
-QUBOTools = "0.9"
-julia = "1.9"
+QUBOTools                 = "0.9"
+julia                     = "1.9"

src/attributes/compiler.jl

@@ -162,7 +162,7 @@ When set, this boolean flag guarantees that every coefficient in the final formu
 struct Discretize <: CompilerAttribute end
 
 function MOI.get(model::Optimizer, ::Discretize)::Bool
-    return get(model.compiler_settings, :discretize, false)
+    return get(model.compiler_settings, :discretize, true)
 end
 
 function MOI.set(model::Optimizer, ::Discretize, flag::Bool)

src/compiler/constraints.jl

@@ -83,7 +83,9 @@ function constraint(
     # Scalar Affine Equality Constraint: g(x) = a'x - b = 0
     g = _parse(model, f, s, arch)
 
-    PBO.discretize!(g)
+    if Attributes.discretize(model)
+        PBO.discretize!(g)
+    end
 
     # Bounds & Slack Variable 
     l, u = PBO.bounds(g)
@@ -136,7 +138,9 @@ function constraint(
     # Scalar Affine Inequality Constraint: g(x) = a'x - b ≤ 0 
     g = _parse(model, f, s, arch)
 
-    PBO.discretize!(g)
+    if Attributes.discretize(model)
+        PBO.discretize!(g)
+    end
 
     # Bounds & Slack Variable 
     l, u = PBO.bounds(g)
@@ -152,9 +156,12 @@ function constraint(
     end
 
     # Slack Variable
-    e = Attributes.slack_variable_encoding_method(model, ci)
     S = (zero(T), abs(l))
-    z = Encoding.encode!(model, ci, e, S)
+    z = if Attributes.discretize(model)
+        variable_ℤ!(model, ci, S)
+    else
+        variable_ℝ!(model, ci, S)
+    end
 
     for (ω, c) in Virtual.expansion(z)
         g[ω] += c
@@ -198,7 +205,9 @@ function constraint(
     # Scalar Affine Inequality Constraint: g(x) = a'x - b ≥ 0 
     g = _parse(model, f, s, arch)
 
-    PBO.discretize!(g)
+    if Attributes.discretize(model)
+        PBO.discretize!(g)
+    end
 
     # Bounds & Slack Variable 
     l, u = PBO.bounds(g)
@@ -214,9 +223,12 @@ function constraint(
     end
 
     # Slack Variable
-    e = Attributes.slack_variable_encoding_method(model, ci)
     S = (zero(T), abs(u))
-    z = Encoding.encode!(model, ci, e, S)
+    z = if Attributes.discretize(model)
+        variable_ℤ!(model, ci, S)
+    else
+        variable_ℝ!(model, ci, S)
+    end
 
     for (ω, c) in Virtual.expansion(z)
         g[ω] -= c
@@ -260,7 +272,9 @@ function constraint(
     # Scalar Quadratic Equality Constraint: g(x) = x' Q x + a' x - b = 0
     g = _parse(model, f, s, arch)
 
-    PBO.discretize!(g)
+    if Attributes.discretize(model)
+        PBO.discretize!(g)
+    end
 
     # Bounds & Slack Variable 
     l, u = PBO.bounds(g)
@@ -320,7 +334,9 @@ function constraint(
     # Scalar Quadratic Inequality Constraint: g(x) = x' Q x + a' x - b ≤ 0
     g = _parse(model, f, s, arch)
 
-    PBO.discretize!(g)
+    if Attributes.discretize(model)
+        PBO.discretize!(g)
+    end
 
     # Bounds & Slack Variable 
     l, u = PBO.bounds(g)
@@ -339,9 +355,12 @@ function constraint(
     end
 
     # Slack Variable
-    e = Attributes.slack_variable_encoding_method(model, ci)
     S = (zero(T), abs(l))
-    z = Encoding.encode!(model, ci, e, S)
+    z = if Attributes.discretize(model)
+        variable_ℤ!(model, ci, S)
+    else
+        variable_ℝ!(model, ci, S)
+    end
 
     for (ω, c) in Virtual.expansion(z)
         g[ω] += c
@@ -388,7 +407,9 @@ function constraint(
     # Scalar Quadratic Inequality Constraint: g(x) = x' Q x + a' x - b ≥ 0
     g = _parse(model, f, s, arch)
 
-    PBO.discretize!(g)
+    if Attributes.discretize(model)
+        PBO.discretize!(g)
+    end
 
     # Bounds & Slack Variable 
     l, u = PBO.bounds(g)
@@ -404,9 +425,12 @@ function constraint(
     end
 
     # Slack Variable
-    e = Attributes.slack_variable_encoding_method(model, ci)
     S = (zero(T), abs(u))
-    z = Encoding.encode!(model, ci, e, S)
+    z = if Attributes.discretize(model)
+        variable_ℤ!(model, ci, S)
+    else
+        variable_ℝ!(model, ci, S)
+    end
 
     for (ω, c) in Virtual.expansion(z)
         g[ω] -= c
@@ -475,8 +499,7 @@ function constraint(
     end
 
     # Slack variable
-    e = Encoding.Mirror{T}()
-    z = Encoding.encode!(model, ci, e)
+    z = variable_𝔹!(model, ci)
 
     for (ω, c) in Virtual.expansion(z)
         g[ω] += c

src/compiler/variables.jl

@@ -71,12 +71,17 @@ function variables!(model::Virtual.Model{T}, ::AbstractArchitecture) where {T}
         end
     end
 
-    # Encode Variables
     if Attributes.stable_compilation(model)
         sort!(Ω; by = x -> x.value)
     end
-
+
+    # Encode Variables
     for x in Ω
+        # If variable was already encoded, skip
+        if haskey(model.source, x)
+            continue
+        end
+
         if haskey(ℤ, x)
             variable_ℤ!(model, x, ℤ[x])
         elseif haskey(ℝ, x)
@@ -89,29 +94,37 @@ function variables!(model::Virtual.Model{T}, ::AbstractArchitecture) where {T}
     return nothing
 end
 
-function variable_𝔹!(model::Virtual.Model{T}, x::VI) where {T}
-    Encoding.encode!(model, x, Encoding.Mirror{T}())
-
-    return nothing
+function variable_𝔹!(model::Virtual.Model{T}, i::Union{VI,CI}) where {T}
+    return Encoding.encode!(model, i, Encoding.Mirror{T}())
 end
 
-function variable_ℤ!(model::Virtual.Model{T}, x::VI, (a, b)::Tuple{T,T}) where {T}
+function variable_ℤ!(model::Virtual.Model{T}, vi::VI, (a, b)::Tuple{T,T}) where {T}
     if isnothing(a) || isnothing(b)
-        error("Unbounded variable $(x) ∈ ℤ")
+        error("Unbounded variable $(vi) ∈ ℤ")
     else
-        let e = Attributes.variable_encoding_method(model, x)
+        let e = Attributes.variable_encoding_method(model, vi)
             S = (a, b)
 
-            Encoding.encode!(model, x, e, S)
+            return Encoding.encode!(model, vi, e, S)
         end
     end
+end
 
-    return nothing
+function variable_ℤ!(model::Virtual.Model{T}, ci::CI, (a, b)::Tuple{T,T}) where {T}
+    if isnothing(a) || isnothing(b)
+        error("Unbounded variable $(ci) ∈ ℤ")
+    else
+        let e = Attributes.slack_variable_encoding_method(model, ci)
+            S = (a, b)
+
+            return Encoding.encode!(model, ci, e, S)
+        end
+    end
 end
 
-function variable_ℝ!(model::Virtual.Model{T}, x::VI, (a, b)::Tuple{T,T}) where {T}
+function variable_ℝ!(model::Virtual.Model{T}, vi::VI, (a, b)::Tuple{T,T}) where {T}
     if isnothing(a) || isnothing(b)
-        error("Unbounded variable $(x) ∈ ℝ")
+        error("Unbounded variable $(vi) ∈ ℝ")
     else
         # TODO: Solve this bit-guessing magic??? (DONE)
         # IDEA: 
@@ -122,23 +135,40 @@ function variable_ℝ!(model::Virtual.Model{T}, x::VI, (a, b)::Tuple{T,T}) where
         #
         #     For 𝔼[|xᵢ - x̂|] ≤ τ we have
         #       N ≥ log₂(1 + |b - a| / 4τ)
-        #
+        # 
         # where τ is the (absolute) tolerance
         # TODO: Add τ as parameter (DONE)
         # TODO: Move this comment to the documentation
-        let e = Attributes.variable_encoding_method(model, x)
-            n = Attributes.variable_encoding_bits(model, x)
+        let e = Attributes.variable_encoding_method(model, vi)
+            n = Attributes.variable_encoding_bits(model, vi)
             S = (a, b)
 
             if !isnothing(n)
-                Encoding.encode!(model, x, e, S, n)
+                return Encoding.encode!(model, vi, e, S, n)
             else
-                tol = Attributes.variable_encoding_atol(model, x)
+                tol = Attributes.variable_encoding_atol(model, vi)
 
-                Encoding.encode!(model, x, e, S; tol)
+                return Encoding.encode!(model, vi, e, S; tol)
             end
         end
     end
+end
 
-    return nothing
+function variable_ℝ!(model::Virtual.Model{T}, ci::CI, (a, b)::Tuple{T,T}) where {T}
+    if isnothing(a) || isnothing(b)
+        error("Unbounded slack variable $(ci) ∈ ℝ")
+    else
+        let e = Attributes.slack_variable_encoding_method(model, ci)
+            n = Attributes.slack_variable_encoding_bits(model, ci)
+            S = (a, b)
+
+            if !isnothing(n)
+                return Encoding.encode!(model, ci, e, S, n)
+            else
+                tol = Attributes.slack_variable_encoding_atol(model, ci)
+
+                return Encoding.encode!(model, ci, e, S; tol)
+            end
+        end
+    end
 end

src/encoding/variables/interval/binary.jl

@@ -37,7 +37,12 @@ function encode(var::Function, e::Binary{T}, S::Tuple{T,T}; tol::Union{T,Nothing
 
     a, b = integer_interval(S)
 
-    @assert b > a
+    if a == b
+        y = VI[]
+        ξ = PBO.PBF{VI,T}(a)
+
+        return (y, ξ, nothing)
+    end
 
     M = trunc(Int, b - a)
     N = ceil(Int, log2(M + 1))
@@ -56,7 +61,7 @@ function encode(var::Function, e::Binary{T}, S::Tuple{T,T}; tol::Union{T,Nothing
         )
     end
 
-    return (y, ξ, nothing) # No penalty function
+    return (y, ξ, nothing)
 end
 
 function encoding_bits(::Binary{T}, S::Tuple{T,T}, tol::T) where {T}

test/integration/examples/quadratic/quadratic.jl

@@ -1,9 +1,11 @@
 include("quadratic_1.jl")
+include("quadratic_2.jl")
 include("primes.jl")
 
 function test_quadratic()
     @testset "Quadratic Programs" verbose = true begin
         test_quadratic_1()
+        test_quadratic_2()
         test_primes()
     end
 end

test/integration/examples/quadratic/quadratic_2.jl

@@ -0,0 +1,34 @@
+QUBOTools.PBO.varshow(v::VI) = QUBOTools.PBO.varshow(v.value)
+
+
+"""
+min x₁ + x₂
+ st x₁² + x₂² >= 1
+    x₁, x₂ ∈ {0, 1}
+
+min x₁ + x₂ + ρ (x₁² + x₂² - 1 + s)²
+    st x₁, x₂ ∈ {0, 1}
+       s ∈ [0, 1]
+
+"""
+function test_quadratic_2()
+    model = Model(() -> ToQUBO.Optimizer())
+
+    @variable(model, x[1:2], Bin)
+    @objective(model, Min, x[1] + x[2])
+    @constraint(model, c, x[1] * x[2] >= 1)
+
+    optimize!(model)
+
+    n, l, q, α, β = QUBOTools.qubo(model, :dense)
+
+    Q = q + diagm(l)
+
+    @show n
+    @show Q
+
+    @test termination_status(model) === MOI.LOCALLY_SOLVED
+    @test get_attribute(model, Attributes.CompilationStatus()) === MOI.LOCALLY_SOLVED
+
+    return nothing
+end