Fix typo, rename states to spin_states, add tests

src/ising.jl

@@ -1,12 +1,12 @@
 ### Helper Functions for Classical Ising Models ###
 
 
-function eval_ising_state_energy(state::Vector, ising_model::Dict)
+function eval_ising_state_energy(spin_state::Vector, ising_model::Dict)
     energy = 0.0
     for (ids,v) in ising_model
         val = v
         for qid in ids
-            val *= state[qid]
+            val *= spin_state[qid]
         end
         energy += val
     end
@@ -26,7 +26,7 @@ function compute_state_energies(ising_model::Dict)
     return state_energy
 end
 
-function print_state_enrgies(ising_model::Dict)
+function print_state_energies(ising_model::Dict)
     state_energies = compute_state_energies(ising_model)
 
     energy_levels = Dict{Float64,Set{Int}}()
@@ -52,4 +52,4 @@ function print_state_enrgies(ising_model::Dict)
         end
     end
 
-end
+end

test/base.jl

@@ -39,6 +39,34 @@
 
 end
 
+@testset "ising energy computations" begin
+    @testset "single qubit, single state" begin
+        @test isapprox(eval_ising_state_energy([1],Dict((1,) => 1)), 1)
+        @test isapprox(eval_ising_state_energy([-1],Dict((1,) => 1)), -1)
+    end
+
+    @testset "single qubit, all states" begin
+        energies = compute_state_energies(Dict((1,) => 1))
+        @test isapprox(energies[0], 1)
+        @test isapprox(energies[1], -1)
+    end
+
+    @testset "double qubit, single state" begin
+        ising_model = Dict((1,) => 1, (2,) => 1, (1,2) => -1)
+        @test isapprox(eval_ising_state_energy([1, 1], ising_model), 1)
+        @test isapprox(eval_ising_state_energy([1, -1], ising_model), 1)
+        @test isapprox(eval_ising_state_energy([-1, 1], ising_model), 1)
+        @test isapprox(eval_ising_state_energy([-1, -1], ising_model), -3)
+    end
+
+    @testset "double qubit, all states" begin
+        energies = compute_state_energies(Dict((1,) => 1, (2,) => 1, (1,2) => -1))
+        @test isapprox(energies[0], 1)
+        @test isapprox(energies[1], 1)
+        @test isapprox(energies[2], 1)
+        @test isapprox(energies[3], -3)
+    end 
+end
 
 @testset "csv annealing schedules" begin
     s_100 = range(0, 1, length=100)