Unverified Commit 1334763b authored by Chaves Claudino, Daniel's avatar Chaves Claudino, Daniel Committed by GitHub
Browse files

Merge pull request #118 from danclaudino/basis_rotations 

Enabled execute with basis rotations
parents 68a03ddc a29bf68b

tnqvm/TNQVM.cpp

+61 −0
Original line number Diff line number Diff line
@@ -138,6 +138,67 @@ void TNQVM::execute(std::shared_ptr<xacc::AcceleratorBuffer> buffer, 
  visitor->finalize();

}



void TNQVM::execute(

std::shared_ptr<AcceleratorBuffer> buffer,

          const std::shared_ptr<CompositeInstruction> baseCircuit,

          const std::vector<std::shared_ptr<CompositeInstruction>> basisRotations) {



  auto provider = xacc::getIRProvider("quantum");

  visitor = xacc::getService<TNQVMVisitor>(getVisitorName())->clone();

  // If in VQE mode and there are more than one kernels

  if (vqeMode && basisRotations.size() > 1 && visitor->supportVqeMode()) {



    visitor->setOptions(options);

    // Nearest neighbor transform:

    if (visitor->name() == "itensor-mps" || visitor->name() == "exatn-mps" ||

        visitor->name() == "exatn-pmps") {

      auto opt = xacc::getService<xacc::IRTransformation>("nnizer");

      opt->apply(baseCircuit, nullptr,

                 {std::make_pair("max-distance", 1)});

    }

    // Initialize the visitor

    visitor->initialize(buffer, getShotCountOption(options));

    visitor->setKernelName(baseCircuit->name());

    xacc::info("Number of instructions: " +

               std::to_string(baseCircuit->nInstructions()));

    // Walk the base IR tree, and visit each node

    InstructionIterator it(baseCircuit);

    while (it.hasNext()) {

      auto nextInst = it.next();

      if (nextInst->isEnabled() && !nextInst->isComposite()) {

        nextInst->accept(visitor);

      }

    }



    // Now we have a wavefunction that represents execution of the ansatz.

    // Run the observable sub-circuits (change of basis + measurements)

    for (int i = 0; i < basisRotations.size(); ++i) {

      auto tmpBuffer = std::make_shared<xacc::AcceleratorBuffer>(

          basisRotations[i]->name(), buffer->size());

      auto obsCircuit = provider->createComposite(basisRotations[i]->name());

      obsCircuit->addInstructions(basisRotations[i]->getInstructions());

      double e = visitor->getExpectationValueZ(obsCircuit);

      tmpBuffer->addExtraInfo("exp-val-z", e);

      buffer->appendChild(obsCircuit->name(), tmpBuffer);

    }

    // Finalize the visitor

    visitor->finalize();

  }

  // Normal execution mode

  else {

    for (auto b : basisRotations) {

      auto tmpBuffer =

          std::make_shared<xacc::AcceleratorBuffer>(b->name(), buffer->size());

      auto obsCircuit = provider->createComposite(b->name());

      obsCircuit->addInstructions(b->getInstructions());

      execute(tmpBuffer, obsCircuit);

      buffer->appendChild(b->name(), tmpBuffer);

    }

  }



  return;

}



const std::vector<std::complex<double>>

TNQVM::getAcceleratorState(std::shared_ptr<CompositeInstruction> program) {

  // Get the visitor backend

tnqvm/TNQVM.hpp

+5 −0
Original line number Diff line number Diff line
@@ -132,6 +132,11 @@ public: 
  void execute(std::shared_ptr<AcceleratorBuffer> buffer,

               const std::vector<std::shared_ptr<CompositeInstruction>> functions) override;



  virtual void

  execute(std::shared_ptr<AcceleratorBuffer> buffer,

          const std::shared_ptr<CompositeInstruction> baseCircuit,

          const std::vector<std::shared_ptr<CompositeInstruction>> basisRotations) override;



  const std::vector<std::complex<double>>

  getAcceleratorState(std::shared_ptr<CompositeInstruction> program) override;