Add Data Tools (#11)

* minor fixes to docs and code comments
* add spin2int, int2spin, spin2binary, closes #6
* add limit and sort features to print_z_state_probabilities
* add note to changelog

Co-authored-by: zmorrell <zmorrell7@gmail.com>

CHANGELOG.md

@@ -2,7 +2,7 @@ QuantumAnnealing.jl Change Log
 ==============================
 
 ### Staged
-- nothing
+- Add data processing tools (#6)
 
 ### v0.0.1
 - Initial release

README.md

@@ -36,7 +36,7 @@ Increase the annealing time to approach the adiabatic limit,
 print_z_state_probabilities(ρ)
 ```
 
-Change the annealing schedule and observer different state probabilities,
+Change the annealing schedule and observe different state probabilities,
 ```
 ρ = simulate(ising_model, 10.0, AS_QUADRATIC)
 print_z_state_probabilities(ρ)

src/base.jl

@@ -68,7 +68,7 @@ converts a integer id into a binary state vector following the package conventio
 valid ints are from 0-to-2^n-1
 pad should be the total number qubits in the system
 """
-function int2binary(x; pad=0)
+function int2binary(x::Int; pad=0)
     return digits(x, base=2, pad=pad)
 end
 
@@ -87,6 +87,30 @@ function binary2spin(states::Vector)
     return [v == 0 ? 1 : -1 for v in states]
 end
 
+"""
+converts a spin state vector into an integer id following the package conventions
+valid ints are from 0-to-2^n-1
+"""
+function spin2int(spin::Vector)
+    return binary2int(spin2binary(spin))
+end
+
+"""
+converts a integer id into a spin state vector following the package conventions
+valid ints are from 0-to-2^n-1
+pad should be the total number qubits in the system
+"""
+function int2spin(x::Int; pad=0)
+    return binary2spin(int2binary(x, pad=pad))
+end
+
+"""
+converts a spin state vector (-1/1) into an binary state vector (0/1)
+"""
+function spin2binary(spin::Vector)
+    return [i == 1 ? 0 : 1 for i in spin]
+end
+
 
 """
 converts a binary state vector into a bra-ket notation string
@@ -116,15 +140,29 @@ end
 
 """
 given a 2^n vector of probably values, prints each value and its associated
-state vector.
+state vector. `limit` is used to limit the total number of states that are
+printed. `sort` is used to re-order the states by most likely instead of the
+default which is numerical order from 0-to-(2^n-1)
 """
-function print_z_state_probabilities(density::Matrix)
+function print_z_state_probabilities(density::Matrix; limit=50, sort=false)
     probs = z_measure_probabilities(density)
     n = ceil(Int, log2(length(probs)))
-    for (i,pr) in enumerate(probs)
-        state = binary2spin(int2binary(i-1, pad=n))
+
+    prob_order = enumerate(probs)
+    if sort
+        prob_order = Base.sort(collect(prob_order), by=(x) -> x[2], rev=true)
+    end
+
+    i = 0
+    for (state_id,pr) in prob_order
+        state = int2spin(state_id-1, pad=n)
         state_string = spin2braket(state)
         prob_string = rpad(round(pr, digits=6),8, " ")
         println("$(prob_string) $(state_string)")
+        i += 1
+        if limit > 0 && i >= limit
+            println("first $(limit) of $(length(probs)) states shown")
+            break
+        end
     end
 end

src/dwave.jl

@@ -66,7 +66,7 @@ function _calc_linear_pwp(x_values, y_values)
 end
 
 
-# construct a spline based piecewise quadratic function
+# construct a spline-based piecewise quadratic function
 function _calc_quadratic_pwp(x_values, y_values)
     @assert(length(x_values) == length(y_values))
 
@@ -154,7 +154,7 @@ function parse_dwave_annealing_schedule(infile; header=1, delim=',', interpolati
         push!(b_values, row[3])
     end
 
-    # rescale based on D-Wave hamiltonian convention
+    # rescale and swap sign based on D-Wave hamiltonian convention
     # https://docs.dwavesys.com/docs/latest/c_qpu_annealing.html
     a_values = a_values ./ -2.0
     b_values = b_values ./ 2.0
@@ -302,7 +302,7 @@ function write_dwisc(outfile::String, ρ, ising_model, qubit_ids; simulated_num_
 
     for state_int in 0:(2^n-1)
         prob = probs[state_int+1]
-        spin_vector = binary2spin(int2binary(state_int, pad=n))
+        spin_vector = int2spin(state_int, pad=n)
         energy = _eval_state_energy(spin_vector, ising_model)
 
         sol_data = Dict(
@@ -341,6 +341,7 @@ function dwave_annealing_protocol(annealing_schedule::AnnealingSchedule; asch=[(
         s1,s_eff_1 = asch[i+1]
         asch_slopes[i] = (s_eff_1 - s_eff_0)/(s1 - s0)
     end
+
     #branchless piecewise function using linear interpolation from y = m*(x-x0) + y0
     function asch_func(s)
         return sum([(asch_slopes[i]*(s-asch[i][1]) + asch[i][2]) * (asch[i][1] <= s < asch[i+1][1]) for i = 1:(length(asch)-1)]) + ((s == asch[end][1])*asch[end][2])

src/simulate.jl

@@ -202,7 +202,6 @@ function simulate(ising_model::Dict, annealing_time::Real, annealing_schedule::A
         Ω2Const = integ2A * constant_bracket_x + integ2B * constant_bracket_z
         Ω2 = (Ω2Sched + Ω2Const)/2
 
-        #display(Ω2)
         U_next = exp(Matrix(-im * (annealing_time*Ω1 + (annealing_time^2)*Ω2)))
         U = U_next * U
 

test/base.jl

@@ -2,6 +2,10 @@
 @testset "state encoding and transformation" begin
 
     @testset "int2binary" begin
+        @test int2binary(0) == []
+        @test int2binary(1) == [1]
+        @test int2binary(2) == [0,1]
+
         @test int2binary(0, pad=3) == [0, 0, 0]
         @test int2binary(1, pad=3) == [1, 0, 0]
         @test int2binary(2, pad=3) == [0, 1, 0]
@@ -10,19 +14,45 @@
         @test int2binary(4, pad=4) == [0, 0, 1, 0]
     end
 
-    @testset "binary2int" begin
+    @testset "int2spin" begin
+        @test int2spin(0) == []
+        @test int2spin(1) == [-1]
+        @test int2spin(2) == [1,-1]
+
+        @test int2spin(0, pad=3) == [ 1,  1,  1]
+        @test int2spin(1, pad=3) == [-1,  1,  1]
+        @test int2spin(2, pad=3) == [ 1, -1,  1]
+        @test int2spin(4, pad=3) == [ 1,  1, -1]
+
+        @test int2spin(4, pad=4) == [1, 1, -1, 1]
+    end
+
+    @testset "int2binary/binary2int" begin
         for i in 0:16
             @test binary2int(int2binary(i, pad=10)) == i
         end
     end
 
+    @testset "int2spin/spin2int" begin
+        for i in 0:16
+            @test spin2int(int2spin(i, pad=10)) == i
+        end
+    end
+
     @testset "binary2spin" begin
         @test binary2spin([0, 0, 0]) == [ 1,  1,  1]
         @test binary2spin([1, 0, 0]) == [-1,  1,  1]
         @test binary2spin([0, 1, 0]) == [ 1, -1,  1]
         @test binary2spin([0, 0, 1]) == [ 1,  1, -1]
     end
 
+    @testset "spin2binary" begin
+        @test spin2binary([ 1,  1,  1]) == [0, 0, 0]
+        @test spin2binary([-1,  1,  1]) == [1, 0, 0]
+        @test spin2binary([ 1, -1,  1]) == [0, 1, 0]
+        @test spin2binary([ 1,  1, -1]) == [0, 0, 1]
+    end
+
     @testset "binary2braket" begin
         @test binary2braket(int2binary(0, pad=3)) == "|000⟩"
         @test binary2braket(int2binary(1, pad=3)) == "|001⟩"
@@ -31,10 +61,10 @@
     end
 
     @testset "binary2braket" begin
-        @test spin2braket(binary2spin(int2binary(0, pad=3))) == "|↑↑↑⟩"
-        @test spin2braket(binary2spin(int2binary(1, pad=3))) == "|↑↑↓⟩"
-        @test spin2braket(binary2spin(int2binary(2, pad=3))) == "|↑↓↑⟩"
-        @test spin2braket(binary2spin(int2binary(4, pad=3))) == "|↓↑↑⟩"
+        @test spin2braket(int2spin(0, pad=3)) == "|↑↑↑⟩"
+        @test spin2braket(int2spin(1, pad=3)) == "|↑↑↓⟩"
+        @test spin2braket(int2spin(2, pad=3)) == "|↑↓↑⟩"
+        @test spin2braket(int2spin(4, pad=3)) == "|↓↑↑⟩"
     end
 
 end

test/data/generate_schedule_csvs.jl

@@ -1,6 +1,6 @@
 using DelimitedFiles
 
-# add a factor of 2x based on D-Wave hamiltonian convention
+# add a factor of 2x and sign inversion based on D-Wave Hamiltonian convention
 # https://docs.dwavesys.com/docs/latest/c_qpu_annealing.html
 A = (s) -> -2.0*cos(π/2*s)
 B = (s) ->  2.0*sin(π/2*s)