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Commit 9a2ebd03 authored by Dmitry I. Lyakh's avatar Dmitry I. Lyakh
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Implemented multi-state eigensolver via Optimizer. 


Signed-off-by: default avatarDmitry I. Lyakh <quant4me@gmail.com>
parent dbb55657
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development.txt
View file @ 9a2ebd03
ISSUES:
- Automatically generated unique tensor names have local scope,
thus the corresponding tensors with automatically generated
names will have their names differ accross different processes.
The only way to ensure proper tensor correspondence in global
tensor operations is to make sure all participating processes
execute the same algorithm in a consistent fashion, like SIMD.
That is, the order of tensor operations across all participating
processes must be consistent such that every encountered global
tensor operation will receive the same tensor operand irrespective
of the difference in the locally generated tensor name. Special
care needs to be taken in iterating over associative tensor containers,
to ensure that the keys are consistent accross all participating
processes. For example, automatically generated tensor names
cannot serve as keys in an iteration procedure since they are
inconsistent accross different processes whereas tensor Ids
can serve as keys since they are normally consistent accross
different processes because the container was built with the
same structure accross all processes.
BUGS:
- 32-bit integer MPI message chunking issue in the backend.
- Fix the bug(s) in the tensor order reduction mechanism in the backend.
- Fix the bug(s) in the tensor order reduction mechanism in the TalshExecutor backend.
FEATURES:
......@@ -14,42 +35,32 @@ FEATURES:
4. Limit the Host buffer size to be similar to the combined devices buffer size;
5. Introduce manual knobs to keep tensors on GPU;
- Implement tensor operator builders.
- TensorExpansion: Constructor that converts a TensorOperator
into a TensorExpansion.
- TensorNetwork: Subnetwork replacement method:
Contract replaced tensors, then replace the contracted
tensor with a new tensor (sub)network.
- Implement SAVE/LOAD API for TensorExpansion.
- Introduce parallelization over tensor networks within a tensor expansion.
- Implement TensorNetwork slice computing Generator.
- Implement b-D procedure.
- Implement constrained optimization for isometric tensors.
- Implement conjugate gradient optimization procedure.
- Implement DIIS convergence accelerator.
- Tensor network bond dimension adaptivity in solvers.
- Implement parameterized non-linear optimization:
dTensorFunctional/dParameter = dTensorFunctional/dTensor * dTensor/dParameter
- Implement conjugate gradient optimization procedure.
- Implement constrained optimization for isometric tensors.
- Fix index slicing logic (switch to two passes):
Pass 1: Compute the throughout volume (TH) for all indices;
TH(index) = Sum of tensor volumes for all tensors containing the index.
Pass 2: Slice indices with maximal throughout volume;
- Implement parameterized non-linear optimization:
dTensorFunctional/dParameter = dTensorFunctional/dTensor * dTensor/dParameter
- Introduce DAG nodes/dependencies with multiple output operands.
- Implement the guided k-way partitioning algorithm.
src/exatn/exatn_numerics.hpp
View file @ 9a2ebd03
/** ExaTN::Numerics: General client header (free function API)
REVISION: 2021/10/19
REVISION: 2021/10/30
Copyright (C) 2018-2021 Dmitry I. Lyakh (Liakh)
Copyright (C) 2018-2021 Oak Ridge National Laboratory (UT-Battelle) **/
......@@ -476,6 +476,14 @@ inline bool initTensorsRndSync(TensorNetwork & tensor_network) //inout: tensor n
{return numericalServer->initTensorsRndSync(tensor_network);}
/** Initializes all input tensors in a given tensor network expansion to a random value. **/
inline bool initTensorsRnd(TensorExpansion & tensor_expansion) //inout: tensor network expansion
{return numericalServer->initTensorsRnd(tensor_expansion);}
inline bool initTensorsRndSync(TensorExpansion & tensor_expansion) //inout: tensor network expansion
{return numericalServer->initTensorsRndSync(tensor_expansion);}
/** Initializes special tensors present in the tensor network. **/
inline bool initTensorsSpecial(TensorNetwork & tensor_network) //inout: tensor network
{return numericalServer->initTensorsSpecial(tensor_network);}
......@@ -971,7 +979,7 @@ inline bool balanceNormalizeNorm2Sync(const ProcessGroup & process_group, //in:
/** Duplicates a given tensor network as a new tensor network copy.
The name of the tensor network copy will be prepended with an underscore
whereas all copies of the input tensors will be renamed with their unique hashes. **/
whereas all copies of the input tensors will be renamed with their unique (local) hashes. **/
inline std::shared_ptr<TensorNetwork> duplicateSync(const TensorNetwork & network) //in: tensor network
{return numericalServer->duplicateSync(network);}
......@@ -981,7 +989,8 @@ inline std::shared_ptr<TensorNetwork> duplicateSync(const ProcessGroup & process
/** Duplicates a given tensor network expansion as a new tensor network expansion copy.
The new tensor network expansion copy will have no name. **/
The name of the tensor network expnasion copy will be prepended with an underscore
whereas all copies of the input tensors will be renamed with their unique (local) hashes. **/
inline std::shared_ptr<TensorExpansion> duplicateSync(const TensorExpansion & expansion) //in: tensor expansion
{return numericalServer->duplicateSync(expansion);}
......
src/exatn/num_server.cpp
View file @ 9a2ebd03
/** ExaTN::Numerics: Numerical server
REVISION: 2021/10/19
REVISION: 2021/10/30
Copyright (C) 2018-2021 Dmitry I. Lyakh (Liakh)
Copyright (C) 2018-2021 Oak Ridge National Laboratory (UT-Battelle) **/
......@@ -8,6 +8,7 @@ Copyright (C) 2018-2021 Oak Ridge National Laboratory (UT-Battelle) **/
#include "tensor_range.hpp"
#include "timers.hpp"
#include <unordered_set>
#include <complex>
#include <vector>
#include <stack>
......@@ -1564,11 +1565,13 @@ bool NumServer::initTensorRndSync(const std::string & name)
bool NumServer::initTensorsRnd(TensorNetwork & tensor_network)
{
bool success = true;
for(auto tens = tensor_network.begin(); tens != tensor_network.end(); ++tens){
std::unordered_set<std::string> tensor_names;
for(auto tens = tensor_network.cbegin(); tens != tensor_network.cend(); ++tens){
auto tensor = tens->second.getTensor();
const auto & tens_name = tensor->getName();
if(tens->first != 0){ //input tensor
if(tensorAllocated(tens_name)){
//auto res = tensor_names.emplace(tens_name);
success = initTensorRnd(tens_name);
}else{
success = false;
......@@ -1578,17 +1581,24 @@ bool NumServer::initTensorsRnd(TensorNetwork & tensor_network)
}
if(!success) break;
}
if(success){
for(const auto & tens_name: tensor_names){
success = initTensorRnd(tens_name); if(!success) break;
}
}
return success;
}
bool NumServer::initTensorsRndSync(TensorNetwork & tensor_network)
{
bool success = true;
for(auto tens = tensor_network.begin(); tens != tensor_network.end(); ++tens){
std::unordered_set<std::string> tensor_names;
for(auto tens = tensor_network.cbegin(); tens != tensor_network.cend(); ++tens){
auto tensor = tens->second.getTensor();
const auto & tens_name = tensor->getName();
if(tens->first != 0){ //input tensor
if(tensorAllocated(tens_name)){
//auto res = tensor_names.emplace(tens_name);
success = initTensorRndSync(tens_name);
}else{
success = false;
......@@ -1598,6 +1608,69 @@ bool NumServer::initTensorsRndSync(TensorNetwork & tensor_network)
}
if(!success) break;
}
if(success){
for(const auto & tens_name: tensor_names){
success = initTensorRndSync(tens_name); if(!success) break;
}
}
return success;
}
bool NumServer::initTensorsRnd(TensorExpansion & tensor_expansion)
{
bool success = true;
std::unordered_set<std::string> tensor_names;
for(auto tensor_network = tensor_expansion.cbegin(); tensor_network != tensor_expansion.cend(); ++tensor_network){
for(auto tens = tensor_network->network->cbegin(); tens != tensor_network->network->cend(); ++tens){
auto tensor = tens->second.getTensor();
const auto & tens_name = tensor->getName();
if(tens->first != 0){ //input tensor
if(tensorAllocated(tens_name)){
//auto res = tensor_names.emplace(tens_name);
success = initTensorRnd(tens_name);
}else{
success = false;
}
}else{ //output tensor
if(tensorAllocated(tens_name)) success = initTensor(tens_name,0.0);
}
if(!success) break;
}
}
if(success){
for(const auto & tens_name: tensor_names){
success = initTensorRnd(tens_name); if(!success) break;
}
}
return success;
}
bool NumServer::initTensorsRndSync(TensorExpansion & tensor_expansion)
{
bool success = true;
std::unordered_set<std::string> tensor_names;
for(auto tensor_network = tensor_expansion.cbegin(); tensor_network != tensor_expansion.cend(); ++tensor_network){
for(auto tens = tensor_network->network->cbegin(); tens != tensor_network->network->cend(); ++tens){
auto tensor = tens->second.getTensor();
const auto & tens_name = tensor->getName();
if(tens->first != 0){ //input tensor
if(tensorAllocated(tens_name)){
//auto res = tensor_names.emplace(tens_name);
success = initTensorRndSync(tens_name);
}else{
success = false;
}
}else{ //output tensor
if(tensorAllocated(tens_name)) success = initTensorSync(tens_name,0.0);
}
if(!success) break;
}
}
if(success){
for(const auto & tens_name: tensor_names){
success = initTensorRndSync(tens_name); if(!success) break;
}
}
return success;
}
......@@ -3241,23 +3314,27 @@ std::shared_ptr<TensorNetwork> NumServer::duplicateSync(const ProcessGroup & pro
{
unsigned int local_rank; //local process rank within the process group
if(!process_group.rankIsIn(process_rank_,&local_rank)) return std::shared_ptr<TensorNetwork>(nullptr); //process is not in the group: Do nothing
bool success = true;
const auto tens_elem_type = network.getTensorElementType();
auto network_copy = makeSharedTensorNetwork(network,true); assert(network_copy);
network_copy->rename("_"+network.getName());
std::unordered_map<std::string,std::shared_ptr<Tensor>> tensor_copies;
for(auto tensor = network_copy->begin(); tensor != network_copy->end(); ++tensor){ //replace input tensors by their copies
if(tensor->first != 0){
const auto & tensor_name = tensor->second.getName();
const auto & tensor_name = tensor->second.getName(); //original tensor name
auto iter = tensor_copies.find(tensor_name);
if(iter == tensor_copies.end()){
auto res = tensor_copies.emplace(std::make_pair(tensor_name,makeSharedTensor(*(tensor->second.getTensor()))));
assert(res.second);
iter = res.first;
iter->second->rename();
iter->second->rename(); //new (automatically generated) tensor name
success = createTensor(iter->second,tens_elem_type); assert(success);
success = copyTensor(iter->second->getName(),tensor_name); assert(success);
}
tensor->second.replaceStoredTensor(iter->second);
}
}
network_copy->rename("_" + network.getName());
auto success = createTensorsSync(process_group,*network_copy,network.getTensorElementType()); assert(success);
success = sync(process_group); assert(success);
return network_copy;
}
......@@ -3271,11 +3348,13 @@ std::shared_ptr<TensorExpansion> NumServer::duplicateSync(const ProcessGroup & p
{
unsigned int local_rank; //local process rank within the process group
if(!process_group.rankIsIn(process_rank_,&local_rank)) return std::shared_ptr<TensorExpansion>(nullptr); //process is not in the group: Do nothing
auto expansion_copy = makeSharedTensorExpansion(expansion.isKet()); assert(expansion_copy);
auto expansion_copy = makeSharedTensorExpansion("_"+expansion.getName(),expansion.isKet());
assert(expansion_copy);
for(auto component = expansion.cbegin(); component != expansion.cend(); ++component){
auto success = expansion_copy->appendComponent(duplicateSync(process_group,*(component->network)),
component->coefficient);
if(!success) return std::shared_ptr<TensorExpansion>(nullptr);
auto dup_network = duplicateSync(process_group,*(component->network));
assert(dup_network);
auto success = expansion_copy->appendComponent(dup_network,component->coefficient);
assert(success);
}
return expansion_copy;
}
......
src/exatn/num_server.hpp
View file @ 9a2ebd03
/** ExaTN::Numerics: Numerical server
REVISION: 2021/10/19
REVISION: 2021/10/30
Copyright (C) 2018-2021 Dmitry I. Lyakh (Liakh)
Copyright (C) 2018-2021 Oak Ridge National Laboratory (UT-Battelle) **/
......@@ -664,6 +664,11 @@ public:
bool initTensorsRndSync(TensorNetwork & tensor_network); //inout: tensor network
/** Initializes all input tensors in a given tensor network expansion to a random value. **/
bool initTensorsRnd(TensorExpansion & tensor_expansion); //inout: tensor network expansion
bool initTensorsRndSync(TensorExpansion & tensor_expansion); //inout: tensor network expansion
/** Initializes special tensors present in the tensor network. **/
bool initTensorsSpecial(TensorNetwork & tensor_network); //inout: tensor network
......@@ -962,14 +967,15 @@ public:
/** Duplicates a given tensor network as a new tensor network copy.
The name of the tensor network copy will be prepended with an underscore
whereas all copies of the input tensors will be renamed with their unique hashes. **/
whereas all copies of the input tensors will be renamed with their unique (local) hashes. **/
std::shared_ptr<TensorNetwork> duplicateSync(const TensorNetwork & network); //in: tensor network
std::shared_ptr<TensorNetwork> duplicateSync(const ProcessGroup & process_group, //in: chosen group of MPI processes
const TensorNetwork & network); //in: tensor network
/** Duplicates a given tensor network expansion as a new tensor network expansion copy.
The new tensor network expansion copy will have no name. **/
The name of the tensor network expansion copy will be prepended with an underscore
whereas all copies of the input tensors will be renamed with their unique (local) hashes. **/
std::shared_ptr<TensorExpansion> duplicateSync(const TensorExpansion & expansion); //in: tensor expansion
std::shared_ptr<TensorExpansion> duplicateSync(const ProcessGroup & process_group, //in: chosen group of MPI processes
......
src/exatn/optimizer.cpp
View file @ 9a2ebd03
/** ExaTN:: Variational optimizer of a closed symmetric tensor network expansion functional
REVISION: 2021/10/22
REVISION: 2021/10/30
Copyright (C) 2018-2021 Dmitry I. Lyakh (Liakh)
Copyright (C) 2018-2021 Oak Ridge National Laboratory (UT-Battelle) **/
......@@ -74,12 +74,28 @@ std::shared_ptr<TensorExpansion> TensorNetworkOptimizer::getSolution(std::comple
}
std::shared_ptr<TensorExpansion> TensorNetworkOptimizer::getSolution(unsigned int root_id,
std::complex<double> * average_expect_val) const
{
assert(root_id < eigenvalues_.size());
if(average_expect_val != nullptr) *average_expect_val = eigenvalues_[root_id];
return eigenvectors_[root_id];
}
std::complex<double> TensorNetworkOptimizer::getExpectationValue() const
{
return average_expect_val_;
}
std::complex<double> TensorNetworkOptimizer::getExpectationValue(unsigned int root_id) const
{
assert(root_id < eigenvalues_.size());
return eigenvalues_[root_id];
}
bool TensorNetworkOptimizer::optimize()
{
return optimize(exatn::getDefaultProcessGroup());
......@@ -92,6 +108,54 @@ bool TensorNetworkOptimizer::optimize(const ProcessGroup & process_group)
}
bool TensorNetworkOptimizer::optimize(unsigned int num_roots)
{
return optimize(exatn::getDefaultProcessGroup(),num_roots);
}
bool TensorNetworkOptimizer::optimize(const ProcessGroup & process_group,
unsigned int num_roots)
{
bool success = true;
auto original_operator = tensor_operator_;
for(unsigned int root_id = 0; root_id < num_roots; ++root_id){
success = initTensorsRndSync(*vector_expansion_); assert(success);
bool synced = sync(process_group); assert(synced);
success = optimize(process_group);
synced = sync(process_group); assert(synced);
if(!success) break;
const auto expect_val = getExpectationValue();
eigenvalues_.emplace_back(expect_val);
auto solution_vector = duplicateSync(process_group,*vector_expansion_);
assert(solution_vector);
success = normalizeNorm2Sync(*solution_vector,1.0); assert(success);
eigenvectors_.emplace_back(solution_vector);
for(auto ket_net = solution_vector->begin(); ket_net != solution_vector->end(); ++ket_net){
ket_net->network->markOptimizableNoTensors();
}
const auto num_legs = solution_vector->getRank();
std::vector<std::pair<unsigned int, unsigned int>> ket_pairing(num_legs);
for(unsigned int i = 0; i < num_legs; ++i) ket_pairing[i] = std::make_pair(i,i);
std::vector<std::pair<unsigned int, unsigned int>> bra_pairing(num_legs);
for(unsigned int i = 0; i < num_legs; ++i) bra_pairing[i] = std::make_pair(i,i);
auto projector = makeSharedTensorOperator("EigenProjector" + std::to_string(root_id));
for(auto ket_net = solution_vector->cbegin(); ket_net != solution_vector->cend(); ++ket_net){
for(auto bra_net = solution_vector->cbegin(); bra_net != solution_vector->cend(); ++bra_net){
success = projector->appendComponent(ket_net->network,bra_net->network,ket_pairing,bra_pairing,
(-expect_val) * std::conj(ket_net->coefficient) * (bra_net->coefficient));
assert(success);
}
}
auto proj_hamiltonian = combineTensorOperators(*tensor_operator_,*projector);
assert(proj_hamiltonian);
tensor_operator_ = proj_hamiltonian;
}
tensor_operator_ = original_operator;
return success;
}
bool TensorNetworkOptimizer::optimize_sd(const ProcessGroup & process_group)
{
constexpr bool NORMALIZE_WITH_METRICS = true; //whether to normalize tensor network factors with metrics or not
......@@ -160,6 +224,7 @@ bool TensorNetworkOptimizer::optimize_sd(const ProcessGroup & process_group)
}
//Prepare derivative environments for all optimizable tensors in the vector expansion:
environments_.clear();
std::unordered_set<std::string> tensor_names;
// Loop over the tensor networks constituting the tensor network vector expansion:
for(auto network = vector_expansion_->cbegin(); network != vector_expansion_->cend(); ++network){
......
src/exatn/optimizer.hpp
View file @ 9a2ebd03
/** ExaTN:: Variational optimizer of a closed symmetric tensor network expansion functional
REVISION: 2021/10/21
REVISION: 2021/10/27
Copyright (C) 2018-2021 Dmitry I. Lyakh (Liakh)
Copyright (C) 2018-2021 Oak Ridge National Laboratory (UT-Battelle) **/
......@@ -10,7 +10,7 @@ Copyright (C) 2018-2021 Oak Ridge National Laboratory (UT-Battelle) **/
vectors formed by the same tensor network expansion, this tensor network
variational optimizer will optimize the tensor factors constituting the
bra/ket tensor network vectors to arrive at an extremum of that functional,
specifically targeting its minimum:
targeting its minimum (or maximum):
E = <x|H|x> / <x|x>, where H is a tensor network operator, and x is a
tensor network expansion that delivers an extremum to the functional.
**/
......@@ -61,16 +61,33 @@ public:
/** Resets the number of micro-iterations. **/
void resetMicroIterations(unsigned int micro_iterations = DEFAULT_MICRO_ITERATIONS);
/** Optimizes the given closed symmetric tensor network expansion functional. **/
/** Optimizes the given closed symmetric tensor network expansion
functional for its minimum (or maximum). **/
bool optimize();
bool optimize(const ProcessGroup & process_group); //in: executing process group
/** Returns the optimized tensor network expansion forming the optimal bra/ket vectors. **/
/** Returns the optimized tensor network expansion forming the optimal
bra/ket vectors delivering an extremum to the functional. **/
std::shared_ptr<TensorExpansion> getSolution(std::complex<double> * average_expect_val = nullptr) const;
/** Returns the achieved expectation value. **/
/** Returns the achieved expectation value of the optimized functional. **/
std::complex<double> getExpectationValue() const;
/** Performs a consecutive tensor network functional optimization
delivering multiple extreme eigenvalues/eigenvectors. **/
bool optimize(unsigned int num_roots); //in: number of extreme roots to find
bool optimize(const ProcessGroup & process_group, //in: executing process group
unsigned int num_roots); //in: number of extreme roots to find
/** Returns a specific extreme root (eigenvalue/eigenvector pair). **/
std::shared_ptr<TensorExpansion> getSolution(unsigned int root_id,
std::complex<double> * average_expect_val = nullptr) const;
/** Returns a specific extreme eigenvalue. **/
std::complex<double> getExpectationValue(unsigned int root_id) const;
/** Enables/disables coarse-grain parallelization over tensor networks. **/
void enableParallelization(bool parallel = true);
......@@ -95,6 +112,9 @@ private:
std::complex<double> expect_value; //current expectation value
};
std::vector<std::shared_ptr<TensorExpansion>> eigenvectors_; //extreme eigenvectors
std::vector<std::complex<double>> eigenvalues_; //extreme eigenvalues
std::shared_ptr<TensorOperator> tensor_operator_; //tensor network operator
std::shared_ptr<TensorExpansion> vector_expansion_; //tensor network expansion to optimize (bra/ket vector)
unsigned int max_iterations_; //max number of macro-iterations
......
src/exatn/tests/NumServerTester.cpp
View file @ 9a2ebd03
......@@ -18,7 +18,7 @@
#include "errors.hpp"
//Test activation:
/*#define EXATN_TEST0
#define EXATN_TEST0
#define EXATN_TEST1
#define EXATN_TEST2
#define EXATN_TEST3
......@@ -48,9 +48,9 @@
//#define EXATN_TEST27 //requires input file from source
//#define EXATN_TEST28 //requires input file from source
#define EXATN_TEST29
#define EXATN_TEST30*/
#define EXATN_TEST31
//#define EXATN_TEST32
#define EXATN_TEST30
//#define EXATN_TEST31 //requires input file from source
#define EXATN_TEST32
#ifdef EXATN_TEST0
......@@ -3603,6 +3603,7 @@ TEST(NumServerTester, ExcitedMCVQE) {
const int max_bond_dim = std::min(static_cast<int>(std::pow(2,num_spin_sites/2)),bond_dim_lim);
const int arity = 2;
const std::string tn_type = "TTN"; //MPS or TTN
const double accuracy = 2e-4;
//exatn::resetLoggingLevel(2,2); //debug
......@@ -3646,11 +3647,11 @@ TEST(NumServerTester, ExcitedMCVQE) {
success = exatn::createTensorsSync(*vec_net2,TENS_ELEM_TYPE); assert(success);
success = exatn::initTensorsRndSync(*vec_net2); assert(success);
std::cout << "Ok" << std::endl;
#if 0
//Ground state search for the original Hamiltonian:
std::cout << "Ground state search for the original Hamiltonian:" << std::endl;
exatn::TensorNetworkOptimizer::resetDebugLevel(1,0);
exatn::TensorNetworkOptimizer optimizer0(hamiltonian0,vec_tns0,5e-4);
exatn::TensorNetworkOptimizer optimizer0(hamiltonian0,vec_tns0,accuracy);
success = exatn::sync(); assert(success);
bool converged = optimizer0.optimize();
success = exatn::sync(); assert(success);
......@@ -3674,7 +3675,7 @@ TEST(NumServerTester, ExcitedMCVQE) {
ket_pairing,bra_pairing,-expect_val0);
auto hamiltonian1 = exatn::combineTensorOperators(*hamiltonian0,*projector0);
exatn::TensorNetworkOptimizer::resetDebugLevel(1,0);
exatn::TensorNetworkOptimizer optimizer1(hamiltonian1,vec_tns1,5e-4);
exatn::TensorNetworkOptimizer optimizer1(hamiltonian1,vec_tns1,accuracy);
success = exatn::sync(); assert(success);
converged = optimizer1.optimize();
success = exatn::sync(); assert(success);
......@@ -3694,7 +3695,7 @@ TEST(NumServerTester, ExcitedMCVQE) {
ket_pairing,bra_pairing,-expect_val1);
auto hamiltonian2 = exatn::combineTensorOperators(*hamiltonian1,*projector1);
exatn::TensorNetworkOptimizer::resetDebugLevel(1,0);
exatn::TensorNetworkOptimizer optimizer2(hamiltonian2,vec_tns2,5e-4);
exatn::TensorNetworkOptimizer optimizer2(hamiltonian2,vec_tns2,accuracy);
success = exatn::sync(); assert(success);
converged = optimizer2.optimize();
success = exatn::sync(); assert(success);
......@@ -3706,6 +3707,28 @@ TEST(NumServerTester, ExcitedMCVQE) {
}
const auto expect_val2 = optimizer2.getExpectationValue();
std::cout << "Expectation value = " << expect_val2 << std::endl;
#endif
//Ground and three excited states in one call:
std::cout << "Ground and three excited states search for the original Hamiltonian:" << std::endl;
exatn::TensorNetworkOptimizer::resetDebugLevel(1,0);
vec_net0->markOptimizableAllTensors();
success = exatn::initTensorsRndSync(*vec_tns0); assert(success);
exatn::TensorNetworkOptimizer optimizer3(hamiltonian0,vec_tns0,accuracy);
success = exatn::sync(); assert(success);
bool converged = optimizer3.optimize(4);
success = exatn::sync(); assert(success);
if(exatn::getProcessRank() == 0){
if(converged){
std::cout << "Search succeeded:" << std::endl;
for(unsigned int root_id = 0; root_id < 4; ++root_id){
std::cout << "Expectation value " << root_id << " = "
<< optimizer3.getExpectationValue(root_id) << std::endl;
}
}else{
std::cout << "Search failed!" << std::endl;
assert(false);
}
}
}
//Synchronize:
......
src/numerics/tensor_operator.cpp
View file @ 9a2ebd03
/** ExaTN::Numerics: Tensor operator
REVISION: 2021/10/26
REVISION: 2021/10/29
Copyright (C) 2018-2021 Dmitry I. Lyakh (Liakh)
Copyright (C) 2018-2021 Oak Ridge National Laboratory (UT-Battelle) **/
......@@ -31,14 +31,7 @@ TensorOperator::TensorOperator(const std::string & name,
const std::complex<double> coefficient):
name_(name)
{
auto shifted_bra_pairing = bra_pairing;
const auto shift = ket_network->getRank();
for(auto & pairing: shifted_bra_pairing) pairing.second += shift;
auto combined_network = makeSharedTensorNetwork(*ket_network,true,ket_network->getName());
combined_network->conjugate();
auto success = combined_network->appendTensorNetwork(TensorNetwork(*bra_network,true,bra_network->getName()),{});
assert(success);
success = appendComponent(combined_network,ket_pairing,shifted_bra_pairing,coefficient);
auto success = appendComponent(ket_network,bra_network,ket_pairing,bra_pairing,coefficient);
assert(success);
}
......@@ -192,6 +185,23 @@ bool TensorOperator::appendSymmetrizeComponent(std::shared_ptr<Tensor> tensor,
}
bool TensorOperator::appendComponent(std::shared_ptr<TensorNetwork> ket_network,
std::shared_ptr<TensorNetwork> bra_network,
const std::vector<std::pair<unsigned int, unsigned int>> & ket_pairing,
const std::vector<std::pair<unsigned int, unsigned int>> & bra_pairing,
const std::complex<double> coefficient)
{
auto shifted_bra_pairing = bra_pairing;
const auto shift = ket_network->getRank();
for(auto & pairing: shifted_bra_pairing) pairing.second += shift;
auto combined_network = makeSharedTensorNetwork(*ket_network,true,ket_network->getName());
combined_network->conjugate();
auto success = combined_network-&g