adding more circuit generators, rdm and vqe energy algoritms, and rdm purification decorator

Signed-off-by: Alex McCaskey <mccaskeyaj@ornl.gov>

quantum/plugins/CMakeLists.txt

+add_subdirectory(ibm)
+#add_subdirectory(rigetti)
+#add_subdirectory(cmr)
+#add_subdirectory(dwave)
+add_subdirectory(algorithms)
+add_subdirectory(decorators)
+add_subdirectory(circuits)
+
+#add_subdirectory(scaffold)
+add_subdirectory(xasm)

quantum/plugins/algorithms/CMakeLists.txt

+add_subdirectory(vqe)
+add_subdirectory(rdm)
+add_subdirectory(vqe-energy)
+#file(GLOB PYDECORATORS ${CMAKE_CURRENT_SOURCE_DIR}/vqe/python/*.py ${CMAKE_CURRENT_SOURCE_DIR}/vqe-energy/python/*.py)
+#install(FILES ${PYDECORATORS} DESTINATION ${CMAKE_INSTALL_PREFIX}/py-plugins)

quantum/plugins/algorithms/rdm/CMakeLists.txt

+
+set(LIBRARY_NAME xacc-algorithm-rdm)
+
+file(GLOB SRC *.cpp)
+
+usfunctiongetresourcesource(TARGET ${LIBRARY_NAME} OUT SRC)
+usfunctiongeneratebundleinit(TARGET ${LIBRARY_NAME} OUT SRC)
+
+add_library(${LIBRARY_NAME} SHARED ${SRC})
+
+target_include_directories(
+  ${LIBRARY_NAME}
+  PUBLIC . ${CMAKE_SOURCE_DIR}/tpls/eigen)
+
+target_link_libraries(${LIBRARY_NAME} PUBLIC xacc CppMicroServices xacc-fermion)
+
+set(_bundle_name xacc_algorithm_rdm)
+set_target_properties(${LIBRARY_NAME}
+                      PROPERTIES COMPILE_DEFINITIONS
+                                 US_BUNDLE_NAME=${_bundle_name}
+                                 US_BUNDLE_NAME
+                                 ${_bundle_name})
+
+usfunctionembedresources(TARGET
+                         ${LIBRARY_NAME}
+                         WORKING_DIRECTORY
+                         ${CMAKE_CURRENT_SOURCE_DIR}
+                         FILES
+                         manifest.json)
+
+if(APPLE)
+  set_target_properties(${LIBRARY_NAME}
+                        PROPERTIES INSTALL_RPATH "@loader_path/../lib")
+  set_target_properties(${LIBRARY_NAME}
+                        PROPERTIES LINK_FLAGS "-undefined dynamic_lookup")
+else()
+  set_target_properties(${LIBRARY_NAME}
+                        PROPERTIES INSTALL_RPATH "$ORIGIN/../lib")
+  set_target_properties(${LIBRARY_NAME} PROPERTIES LINK_FLAGS "-shared")
+endif()
+
+if(XACC_BUILD_TESTS)
+  add_subdirectory(tests)
+endif()
+
+install(TARGETS ${LIBRARY_NAME} DESTINATION ${CMAKE_INSTALL_PREFIX}/plugins)

quantum/plugins/algorithms/rdm/RDMActivator.cpp

+#include "rdm.hpp"
+
+#include "cppmicroservices/BundleActivator.h"
+#include "cppmicroservices/BundleContext.h"
+#include "cppmicroservices/ServiceProperties.h"
+
+#include <memory>
+#include <set>
+
+using namespace cppmicroservices;
+
+namespace {
+
+/**
+ */
+class US_ABI_LOCAL RDMActivator : public BundleActivator {
+
+public:
+  RDMActivator() {}
+
+  /**
+   */
+  void Start(BundleContext context) {
+    auto c = std::make_shared<xacc::algorithm::RDM>();
+    context.RegisterService<xacc::Algorithm>(c);
+  }
+
+  /**
+   */
+  void Stop(BundleContext /*context*/) {}
+};
+
+} // namespace
+
+CPPMICROSERVICES_EXPORT_BUNDLE_ACTIVATOR(RDMActivator)

quantum/plugins/algorithms/rdm/manifest.json

+{
+  "bundle.symbolic_name" : "xacc_algorithm_rdm",
+  "bundle.activator" : true,
+  "bundle.name" : "XACC RDM Generation Algorithm",
+  "bundle.description" : ""
+}

quantum/plugins/algorithms/rdm/rdm.cpp

+#include "rdm.hpp"
+
+#include "Observable.hpp"
+#include "XACC.hpp"
+
+#include "FermionOperator.hpp"
+#include <unsupported/Eigen/CXX11/Tensor>
+#include <unsupported/Eigen/CXX11/TensorSymmetry>
+
+#include <memory>
+using namespace xacc;
+
+namespace xacc {
+namespace algorithm {
+bool RDM::initialize(const HeterogeneousMap &parameters) {
+  if (!parameters.keyExists<std::shared_ptr<CompositeInstruction>>("ansatz")) {
+    return false;
+  } else if (!parameters.keyExists<std::shared_ptr<Accelerator>>("accelerator")) {
+    return false;
+  }
+
+  ansatz = parameters.get<std::shared_ptr<CompositeInstruction>>("ansatz");
+  accelerator = parameters.get<std::shared_ptr<Accelerator>>("accelerator");
+
+  return true;
+}
+
+const std::vector<std::string> RDM::requiredParameters() const {
+  return {"accelerator", "ansatz"};
+}
+
+void RDM::execute(const std::shared_ptr<AcceleratorBuffer> buffer) const {
+
+  // Reset
+  int nQubits = buffer->size(), nExecs = 0;
+
+  Eigen::Tensor<std::complex<double>, 4> rho_pqrs(nQubits, nQubits, nQubits,
+                                                  nQubits);
+  rho_pqrs.setZero();
+
+  // Get the Accelerator we're running on, the
+  // number of orbitals/qubits in the problem,
+  // the MPIProvider Communicator reference, and the
+  // VQE state preparation ansatz.
+
+  Eigen::DynamicSGroup rho_pq_Sym, rho_pqrs_Sym;
+  rho_pq_Sym.addHermiticity(0, 1);
+  rho_pqrs_Sym.addAntiSymmetry(0, 1);
+  rho_pqrs_Sym.addAntiSymmetry(2, 3);
+
+  // Map p,q,r,s indices to a coefficient for all
+  // identity terms encountered
+  std::map<std::vector<int>, double> rho_element_2_identity_coeff;
+
+  // Map function names to the actual function and all
+  // p,q,r,s and coefficients that contribute to that element
+  std::map<std::string,
+           std::pair<std::shared_ptr<CompositeInstruction>,
+                     std::vector<std::pair<std::vector<int>, double>>>>
+      functions;
+
+  // Generate the 2-RDM circuits for executiong
+  for (int m = 0; m < nQubits; m++) {
+    for (int n = m + 1; n < nQubits; n++) {
+      for (int v = m; v < nQubits; v++) {
+        for (int w = v + 1; w < nQubits; w++) {
+          std::stringstream xx;
+          xx << "0.5 " << m << "^ " << n << "^ " << w << " " << v << " + "
+             << "0.5 " << w << "^ " << v << "^ " << m << " " << n;
+          auto op = std::make_shared<xacc::quantum::FermionOperator>(xx.str());
+          auto hpqrs_ir = op->observe(ansatz);
+
+          for (auto &kernel : hpqrs_ir) {
+            auto t = std::real(
+                kernel->getCoefficient());
+            int nFunctionInstructions = 0;
+
+            if (kernel->getInstruction(0)->isComposite()) {
+              nFunctionInstructions =
+                  ansatz->nInstructions() + kernel->nInstructions() - 1;
+            } else {
+              nFunctionInstructions = kernel->nInstructions();
+            }
+
+            if (nFunctionInstructions > ansatz->nInstructions()) {
+              // if (kernel->nInstructions() > ansatz->nInstructions()) {
+              auto name = kernel->name();
+              if (functions.count(name)) {
+                functions[name].second.push_back({{m, n, v, w}, t});
+              } else {
+                functions.insert({name, {kernel, {{{m, n, v, w}, t}}}});
+              }
+            } else {
+              rho_element_2_identity_coeff.insert({{m, n, v, w}, t});
+            }
+          }
+        }
+      }
+    }
+  }
+
+  std::vector<std::shared_ptr<CompositeInstruction>> fsToExecute;
+  for (auto &kv : functions) {
+    fsToExecute.push_back(kv.second.first);
+  }
+
+  int nPhysicalQubits =
+      nQubits; //*std::max_element(qubitMap.begin(), qubitMap.end()) + 1;
+
+  // Execute all nontrivial circuits
+  xacc::info("[RDM] Executing " + std::to_string(fsToExecute.size()) +
+             " circuits to compute rho_pqrs.");
+  auto tmpBuffer = xacc::qalloc(buffer->size());
+  accelerator->execute(tmpBuffer, fsToExecute);
+  auto buffers = tmpBuffer->getChildren();
+
+  bool useROExps = false;
+  if (accelerator->name() == "ro-error") {
+    useROExps = true;
+  }
+
+  // Create a mapping of rho_pqrs elements to summed expectation values for
+  // each circuit contributing to it
+  std::map<std::vector<int>, double> sumMap;
+  for (int i = 0; i < buffers.size(); i++) {
+    auto fName = fsToExecute[i]->name();
+    auto p = functions[fName];
+    std::vector<std::string> contributingIndices;
+    std::vector<double> contributingCoeffs;
+    for (auto &l : p.second) {
+      auto elements = l.first;
+      std::stringstream s;
+      s << elements[0] << "," << elements[1] << "," << elements[2] << ","
+        << elements[3];
+      contributingIndices.push_back(s.str());
+      double value;
+      if (useROExps) {
+        value = l.second * mpark::get<double>(buffers[i]->getInformation(
+                               "ro-fixed-exp-val-z"));
+      } else {
+        value = l.second * buffers[i]->getExpectationValueZ();
+      }
+      contributingCoeffs.push_back(value);
+      if (!sumMap.count(elements)) {
+        sumMap.insert({elements, value});
+      } else {
+        sumMap[elements] += value;
+      }
+    }
+    buffers[i]->addExtraInfo("kernel", ExtraInfo(fName));
+    buffers[i]->addExtraInfo("contributing_rho_pqrs",
+                             ExtraInfo(contributingIndices));
+    buffers[i]->addExtraInfo("contributing_coeffs",
+                             ExtraInfo(contributingCoeffs));
+    buffer->appendChild(fName, buffers[i]);
+  }
+
+  // Add all identity terms, we don't execute them
+  // but we still have to add their contribution
+  for (auto &kv : rho_element_2_identity_coeff) {
+    sumMap[kv.first] += kv.second;
+  }
+
+  // Set rho_pqrs. This is all we need
+  // to get rho_pq as well
+  for (auto &kv : sumMap) {
+    auto elements = kv.first;
+    rho_pqrs_Sym(rho_pqrs, elements[0], elements[1], elements[2], elements[3]) =
+        kv.second;
+    rho_pqrs_Sym(rho_pqrs, elements[2], elements[3], elements[0], elements[1]) =
+        kv.second;
+  }
+
+  Eigen::Tensor<double, 4> realt = rho_pqrs.real();
+  auto real = realt.data();
+  std::vector<double> rho_pqrs_data(real, real + rho_pqrs.size());
+  for (auto &a : rho_pqrs_data)
+    if (std::fabs(a) < 1e-12)
+      a = 0;
+
+  buffer->addExtraInfo("2-rdm", ExtraInfo(rho_pqrs_data));
+  return;
+}
+} // namespace algorithm
+} // namespace xacc
\ No newline at end of file

quantum/plugins/algorithms/rdm/rdm.hpp

+#ifndef XACC_ALGORITHM_RDM_HPP_
+#define XACC_ALGORITHM_RDM_HPP_
+
+#include "Algorithm.hpp"
+
+namespace xacc {
+namespace algorithm {
+class RDM : public Algorithm {
+protected:
+  std::shared_ptr<CompositeInstruction> ansatz;
+  std::shared_ptr<Accelerator> accelerator;
+
+  HeterogeneousMap parameters;
+
+public:
+  bool initialize(const HeterogeneousMap &parameters) override;
+  const std::vector<std::string> requiredParameters() const override;
+
+  void execute(const std::shared_ptr<AcceleratorBuffer> buffer) const override;
+  const std::string name() const override { return "rdm"; }
+  const std::string description() const override { return ""; }
+};
+} // namespace algorithm
+} // namespace xacc
+#endif
\ No newline at end of file

quantum/plugins/algorithms/rdm/tests/CMakeLists.txt

+include_directories(${CMAKE_BINARY_DIR})
+include_directories(${CMAKE_SOURCE_DIR}/tpls/eigen)
+add_xacc_test(RDM)
+target_link_libraries(RDMTester xacc CppMicroServices xacc-fermion)
\ No newline at end of file

quantum/plugins/algorithms/rdm/tests/RDMTester.cpp

+#include "Instruction.hpp"
+#include "XACC.hpp"
+#include <gtest/gtest.h>
+#include "xacc_service.hpp"
+#include "FermionOperator.hpp"
+#include <unsupported/Eigen/CXX11/Tensor>
+
+using namespace xacc;
+
+const std::string src = R"src(0.7080240949826064
+- 1.248846801817026 0^ 0
+- 1.248846801817026 1^ 1
+- 0.4796778151607899 2^ 2
+- 0.4796778151607899 3^ 3
++ 0.33667197218932576 0^ 1^ 1 0
++ 0.0908126658307406 0^ 1^ 3 2
++ 0.09081266583074038 0^ 2^ 0 2
++ 0.331213646878486 0^ 2^ 2 0
++ 0.09081266583074038 0^ 3^ 1 2
++ 0.331213646878486 0^ 3^ 3 0
++ 0.33667197218932576 1^ 0^ 0 1
++ 0.0908126658307406 1^ 0^ 2 3
++ 0.09081266583074038 1^ 2^ 0 3
++ 0.331213646878486 1^ 2^ 2 1
++ 0.09081266583074038 1^ 3^ 1 3
++ 0.331213646878486 1^ 3^ 3 1
++ 0.331213646878486 2^ 0^ 0 2
++ 0.09081266583074052 2^ 0^ 2 0
++ 0.331213646878486 2^ 1^ 1 2
++ 0.09081266583074052 2^ 1^ 3 0
++ 0.09081266583074048 2^ 3^ 1 0
++ 0.34814578469185886 2^ 3^ 3 2
++ 0.331213646878486 3^ 0^ 0 3
++ 0.09081266583074052 3^ 0^ 2 1
++ 0.331213646878486 3^ 1^ 1 3
++ 0.09081266583074052 3^ 1^ 3 1
++ 0.09081266583074048 3^ 2^ 0 1
++ 0.34814578469185886 3^ 2^ 2 3)src";
+
+const std::string rucc = R"rucc(__qpu__ void f(qbit q, double t0) {
+    X(q[0]);
+    X(q[1]);
+    Rx(q[0],1.5707);
+    H(q[1]);
+    H(q[2]);
+    H(q[3]);
+    CNOT(q[0],q[1]);
+    CNOT(q[1],q[2]);
+    CNOT(q[2],q[3]);
+    Rz(q[3], t0);
+    CNOT(q[2],q[3]);
+    CNOT(q[1],q[2]);
+    CNOT(q[0],q[1]);
+    Rx(q[0],-1.5707);
+    H(q[1]);
+    H(q[2]);
+    H(q[3]);
+})rucc";
+
+TEST(RDMGeneratorTester, checkGround) {
+
+  if (xacc::hasAccelerator("tnqvm")) {
+    // Get the user-specified Accelerator,
+    // or TNQVM if none specified
+    auto accelerator = xacc::getAccelerator("tnqvm");
+    int nQubits = 4;
+
+    xacc::quantum::FermionOperator op(src);
+    Eigen::Tensor<double,2> hpq(4,4); hpq.setZero();
+    Eigen::Tensor<double,4> hpqrs(4,4,4,4);hpqrs.setZero();
+    double enuc = 0.0;
+
+    auto terms = op.getTerms();
+    for (auto& kv : terms) {
+        auto ops = kv.second.ops();
+        if (ops.size() == 4) {
+            hpqrs(ops[0].first,ops[1].first,ops[2].first, ops[3].first) = std::real(kv.second.coeff());
+        } else if (ops.size() == 2) {
+            hpq(ops[0].first,ops[1].first) = std::real(kv.second.coeff());
+        } else {
+            enuc = std::real(kv.second.coeff());
+        }
+    }
+
+    // Create the UCCSD ansatz and evaluate
+    // at the known optimal angles
+    auto compiler = xacc::getCompiler("xasm");
+
+    auto ir2 = compiler->compile(rucc, accelerator);
+    auto ruccsd = ir2->getComposite("f");
+
+    std::vector<double> parameters{.22984};
+    ruccsd = (*ruccsd.get())(parameters);
+
+    // Create the 2-RDM
+    // std::vector<int> qubitMap {1,3,5,7}; // map to physical qubits
+    // ruccsd->mapBits(qubitMap);
+     auto rdmGen = xacc::getAlgorithm("rdm");
+     EXPECT_TRUE(rdmGen->initialize({std::make_pair("accelerator",accelerator ), std::make_pair("ansatz", ruccsd)}));
+     auto buffer = xacc::qalloc(4);
+     rdmGen->execute(buffer);
+    // auto buffers = generator.generate(ruccsd, qubitMap);
+
+    auto data = buffer->getInformation("2-rdm").as<std::vector<double>>();
+
+    // EXPECT_EQ(buffers.size(), 54);
+     Eigen::TensorMap<Eigen::Tensor<double,4>> rho_pqrs(data.data(), 4,4,4,4);
+
+    // // Get the 1 rdm from the 2 rdm
+    Eigen::array<int, 2> cc2({1, 3});
+    Eigen::Tensor<double, 2> rho_pq = rho_pqrs.trace(cc2);
+
+    double energy = enuc;
+    // Compute the 2 rdm contribution to the energy
+    for (int p = 0; p < nQubits; p++) {
+      for (int q = 0; q < nQubits; q++) {
+        for (int r = 0; r < nQubits; r++) {
+          for (int s = 0; s < nQubits; s++) {
+            energy +=
+                0.5 * std::real(hpqrs(p, q, r, s) *
+                                (rho_pqrs(p, q, s, r) + rho_pqrs(r, s, q, p)));
+          }
+        }
+      }
+    }
+
+    // Compute the 1 rdm contribution to the energy
+    for (int p = 0; p < nQubits; p++) {
+      for (int q = 0; q < nQubits; q++) {
+        energy += 0.5 * std::real(hpq(p, q) * (rho_pq(p, q) + rho_pq(q, p)));
+      }
+    }
+    std::cout << "ENERGY: " << energy << "\n";
+
+    // // auto energy = rhoGen.energy();
+    EXPECT_NEAR(energy, -1.1371, 1e-4);
+  }
+}
+
+int main(int argc, char **argv) {
+  xacc::Initialize();
+  int ret = 0;
+  ::testing::InitGoogleTest(&argc, argv);
+  ret = RUN_ALL_TESTS();
+  xacc::Finalize();
+  return ret;
+}

quantum/plugins/algorithms/vqe-energy/CMakeLists.txt

+
+set(LIBRARY_NAME xacc-algorithm-vqe-energy)
+
+file(GLOB SRC *.cpp)
+
+usfunctiongetresourcesource(TARGET ${LIBRARY_NAME} OUT SRC)
+usfunctiongeneratebundleinit(TARGET ${LIBRARY_NAME} OUT SRC)
+
+add_library(${LIBRARY_NAME} SHARED ${SRC})
+
+target_include_directories(
+  ${LIBRARY_NAME}
+  PUBLIC .)
+
+target_link_libraries(${LIBRARY_NAME} PUBLIC xacc CppMicroServices)
+
+set(_bundle_name xacc_algorithm_vqe_energy)
+set_target_properties(${LIBRARY_NAME}
+                      PROPERTIES COMPILE_DEFINITIONS
+                                 US_BUNDLE_NAME=${_bundle_name}
+                                 US_BUNDLE_NAME
+                                 ${_bundle_name})
+
+usfunctionembedresources(TARGET
+                         ${LIBRARY_NAME}
+                         WORKING_DIRECTORY
+                         ${CMAKE_CURRENT_SOURCE_DIR}
+                         FILES
+                         manifest.json)
+
+if(APPLE)
+  set_target_properties(${LIBRARY_NAME}
+                        PROPERTIES INSTALL_RPATH "@loader_path/../lib")
+  set_target_properties(${LIBRARY_NAME}
+                        PROPERTIES LINK_FLAGS "-undefined dynamic_lookup")
+else()
+  set_target_properties(${LIBRARY_NAME}
+                        PROPERTIES INSTALL_RPATH "$ORIGIN/../lib")
+  set_target_properties(${LIBRARY_NAME} PROPERTIES LINK_FLAGS "-shared")
+endif()
+
+if(XACC_BUILD_TESTS)
+  add_subdirectory(tests)
+endif()
+
+install(TARGETS ${LIBRARY_NAME} DESTINATION ${CMAKE_INSTALL_PREFIX}/plugins)

quantum/plugins/algorithms/vqe-energy/VQEEnergyActivator.cpp

+#include "vqe-energy.hpp"
+
+#include "cppmicroservices/BundleActivator.h"
+#include "cppmicroservices/BundleContext.h"
+#include "cppmicroservices/ServiceProperties.h"
+
+#include <memory>
+#include <set>
+
+using namespace cppmicroservices;
+
+namespace {
+
+/**
+ */
+class US_ABI_LOCAL VQEEnergyActivator : public BundleActivator {
+
+public:
+  VQEEnergyActivator() {}
+
+  /**
+   */
+  void Start(BundleContext context) {
+    auto c = std::make_shared<xacc::algorithm::VQEEnergy>();
+    context.RegisterService<xacc::Algorithm>(c);
+  }
+
+  /**
+   */
+  void Stop(BundleContext /*context*/) {}
+};
+
+} // namespace
+
+CPPMICROSERVICES_EXPORT_BUNDLE_ACTIVATOR(VQEEnergyActivator)

quantum/plugins/algorithms/vqe-energy/manifest.json

+{
+  "bundle.symbolic_name" : "xacc_algorithm_vqe_energy",
+  "bundle.activator" : true,
+  "bundle.name" : "XACC VQE-Energy Algorithm",
+  "bundle.description" : ""
+}

quantum/plugins/algorithms/vqe-energy/python/tests/py_energy_test.py

+import unittest as test
+import sys
+import xacc
+from xacc import PauliOperator
+
+class TestPyVQE(test.TestCase):
+
+    def setUp(self):
+        self.qpu = xacc.getAccelerator('tnqvm')
+        self.buffer = self.qpu.createBuffer('q', 2)
+        self.ham = PauliOperator(5.906709445) + \
+                    PauliOperator({0: 'X', 1: 'X'}, -2.1433) + \
+                    PauliOperator({0: 'Y', 1: 'Y'}, -2.1433) + \
+                    PauliOperator({0: 'Z'}, .21829) + \
+                    PauliOperator({1: 'Z'}, -6.125)
+
+    def test_energy(self):
+
+        @xacc.qpu(algo='energy', accelerator=self.qpu, observable=self.ham)
+        def ansatz(buffer, t0):
+            X(0)
+            Ry(t0, 1)
+            CNOT(1, 0)
+
+        ansatz(self.buffer, 0.5)
+
+        self.assertAlmostEqual(self.buffer.getInformation(