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test_model_solver_my_model.hh
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			/**
			* @file test_model_solver_my_model.hh
			*
			* @author Nicolas Richart <nicolas.richart@epfl.ch>
			*
			* @date creation: Wed Apr 13 2016
			* @date last modification: Fri Jun 26 2020
			*
			* @brief Test default dof manager
			*
			*
			* @section LICENSE
			*
			* Copyright (©) 2016-2021 EPFL (Ecole Polytechnique Fédérale de Lausanne)
			* Laboratory (LSMS - Laboratoire de Simulation en Mécanique des Solides)
			*
			* Akantu is free software: you can redistribute it and/or modify it under the
			* terms of the GNU Lesser General Public License as published by the Free
			* Software Foundation, either version 3 of the License, or (at your option) any
			* later version.
			*
			* Akantu is distributed in the hope that it will be useful, but WITHOUT ANY
			* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
			* A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
			* details.
			*
			* You should have received a copy of the GNU Lesser General Public License
			* along with Akantu. If not, see <http://www.gnu.org/licenses/>.
			*
			*/

			/* -------------------------------------------------------------------------- */
			#include "aka_iterators.hh"
			#include "boundary_condition.hh"
			#include "communicator.hh"
			#include "data_accessor.hh"
			#include "dof_manager_default.hh"
			#include "element_synchronizer.hh"
			#include "mesh.hh"
			#include "model_solver.hh"
			#include "periodic_node_synchronizer.hh"
			#include "solver_vector_default.hh"
			#include "sparse_matrix.hh"

			/* -------------------------------------------------------------------------- */

			namespace akantu {

			#ifndef AKANTU_TEST_MODEL_SOLVER_MY_MODEL_HH_
			#define AKANTU_TEST_MODEL_SOLVER_MY_MODEL_HH_

			/**
			* =\o-----o-----o-> F
			* \| \|
			* \|---- L ----\|
			*/
			class MyModel : public ModelSolver,
			public BoundaryCondition<MyModel>,
			public DataAccessor<Element> {
			public:
			MyModel(Real F, Mesh & mesh, bool lumped,
			const ID & dof_manager_type = "default")
			: ModelSolver(mesh, ModelType::_model, "model_solver"),
			nb_dofs(mesh.getNbNodes()), nb_elements(mesh.getNbElement(_segment_2)),
			lumped(lumped), E(1.), A(1.), rho(1.), mesh(mesh),
			displacement(nb_dofs, 1, "disp"), velocity(nb_dofs, 1, "velo"),
			acceleration(nb_dofs, 1, "accel"), blocked(nb_dofs, 1, "blocked"),
			forces(nb_dofs, 1, "force_ext"),
			internal_forces(nb_dofs, 1, "force_int"),
			stresses(nb_elements, 1, "stress"), strains(nb_elements, 1, "strain"),
			initial_lengths(nb_elements, 1, "L0") {

			this->initDOFManager(dof_manager_type);

			this->initBC(*this, displacement, forces);

			this->getDOFManager().registerDOFs("disp", displacement, _dst_nodal);
			this->getDOFManager().registerDOFsDerivative("disp", 1, velocity);
			this->getDOFManager().registerDOFsDerivative("disp", 2, acceleration);
			this->getDOFManager().registerBlockedDOFs("disp", blocked);

			displacement.set(0.);
			velocity.set(0.);
			acceleration.set(0.);

			forces.set(0.);
			blocked.set(false);

			UInt global_nb_nodes = mesh.getNbGlobalNodes();
			for (auto && n : arange(nb_dofs)) {
			auto global_id = mesh.getNodeGlobalId(n);
			if (global_id == (global_nb_nodes - 1))
			forces(n, _x) = F;

			if (global_id == 0)
			blocked(n, _x) = true;
			}

			auto cit = this->mesh.getConnectivity(_segment_2).begin(2);
			auto cend = this->mesh.getConnectivity(_segment_2).end(2);
			auto L_it = this->initial_lengths.begin();

			for (; cit != cend; ++cit, ++L_it) {
			const Vector<UInt> & conn = *cit;
			UInt n1 = conn(0);
			UInt n2 = conn(1);
			Real p1 = this->mesh.getNodes()(n1, _x);
			Real p2 = this->mesh.getNodes()(n2, _x);

			*L_it = std::abs(p2 - p1);
			}

			this->registerDataAccessor(*this);
			this->registerSynchronizer(
			const_cast<ElementSynchronizer &>(this->mesh.getElementSynchronizer()),
			SynchronizationTag::_user_1);
			}

			void assembleLumpedMass() {
			auto & M = this->getDOFManager().getLumpedMatrix("M");
			M.zero();

			this->assembleLumpedMass(_not_ghost);
			if (this->mesh.getNbElement(_segment_2, _ghost) > 0)
			this->assembleLumpedMass(_ghost);

			is_lumped_mass_assembled = true;
			}

			void assembleLumpedMass(GhostType ghost_type) {
			Array<Real> M(nb_dofs, 1, 0.);

			Array<Real> m_all_el(this->mesh.getNbElement(_segment_2, ghost_type), 2);

			for (auto && data :
			zip(make_view(this->mesh.getConnectivity(_segment_2), 2),
			make_view(m_all_el, 2))) {
			const auto & conn = std::get<0>(data);
			auto & m_el = std::get<1>(data);

			UInt n1 = conn(0);
			UInt n2 = conn(1);

			Real p1 = this->mesh.getNodes()(n1, _x);
			Real p2 = this->mesh.getNodes()(n2, _x);

			Real L = std::abs(p2 - p1);

			Real M_n = rho * A * L / 2;
			m_el(0) = m_el(1) = M_n;
			}

			this->getDOFManager().assembleElementalArrayLocalArray(
			m_all_el, M, _segment_2, ghost_type);

			this->getDOFManager().assembleToLumpedMatrix("disp", M, "M");
			}

			void assembleMass() {
			SparseMatrix & M = this->getDOFManager().getMatrix("M");
			M.zero();

			Array<Real> m_all_el(this->nb_elements, 4);

			Matrix<Real> m(2, 2);
			m(0, 0) = m(1, 1) = 2;
			m(0, 1) = m(1, 0) = 1;

			// under integrated
			// m(0, 0) = m(1, 1) = 3./2.;
			// m(0, 1) = m(1, 0) = 3./2.;

			// lumping the mass matrix
			// m(0, 0) += m(0, 1);
			// m(1, 1) += m(1, 0);
			// m(0, 1) = m(1, 0) = 0;

			for (auto && data :
			zip(make_view(this->mesh.getConnectivity(_segment_2), 2),
			make_view(m_all_el, 2, 2))) {
			const auto & conn = std::get<0>(data);
			auto & m_el = std::get<1>(data);
			UInt n1 = conn(0);
			UInt n2 = conn(1);

			Real p1 = this->mesh.getNodes()(n1, _x);
			Real p2 = this->mesh.getNodes()(n2, _x);

			Real L = std::abs(p2 - p1);

			m_el = m;
			m_el = rho A * L / 6.;
			}

			this->getDOFManager().assembleElementalMatricesToMatrix(
			"M", "disp", m_all_el, _segment_2);

			is_mass_assembled = true;
			}

			MatrixType getMatrixType(const ID &) override { return _symmetric; }

			void assembleMatrix(const ID & matrix_id) override {
			if (matrix_id == "K") {
			if (not is_stiffness_assembled)
			this->assembleStiffness();
			} else if (matrix_id == "M") {
			if (not is_mass_assembled)
			this->assembleMass();
			} else if (matrix_id == "C") {
			// pass, no damping matrix
			} else {
			AKANTU_EXCEPTION("This solver does not know what to do with a matrix "
			<< matrix_id);
			}
			}

			void assembleLumpedMatrix(const ID & matrix_id) override {
			if (matrix_id == "M") {
			if (not is_lumped_mass_assembled)
			this->assembleLumpedMass();
			} else {
			AKANTU_EXCEPTION("This solver does not know what to do with a matrix "
			<< matrix_id);
			}
			}

			void assembleStiffness() {
			SparseMatrix & K = this->getDOFManager().getMatrix("K");
			K.zero();

			Matrix<Real> k(2, 2);
			k(0, 0) = k(1, 1) = 1;
			k(0, 1) = k(1, 0) = -1;

			Array<Real> k_all_el(this->nb_elements, 4);

			auto k_it = k_all_el.begin(2, 2);
			auto cit = this->mesh.getConnectivity(_segment_2).begin(2);
			auto cend = this->mesh.getConnectivity(_segment_2).end(2);

			for (; cit != cend; ++cit, ++k_it) {
			const auto & conn = *cit;
			UInt n1 = conn(0);
			UInt n2 = conn(1);

			Real p1 = this->mesh.getNodes()(n1, _x);
			Real p2 = this->mesh.getNodes()(n2, _x);

			Real L = std::abs(p2 - p1);

			auto & k_el = *k_it;
			k_el = k;
			k_el = E A / L;
			}

			this->getDOFManager().assembleElementalMatricesToMatrix(
			"K", "disp", k_all_el, _segment_2);

			is_stiffness_assembled = true;
			}

			void assembleResidual() override {
			this->getDOFManager().assembleToResidual("disp", forces);
			internal_forces.zero();

			this->assembleResidualInternal(_not_ghost);

			this->synchronize(SynchronizationTag::_user_1);

			this->getDOFManager().assembleToResidual("disp", internal_forces, -1.);
			}

			void assembleResidualInternal(GhostType ghost_type) {
			Array<Real> forces_internal_el(
			this->mesh.getNbElement(_segment_2, ghost_type), 2);

			auto cit = this->mesh.getConnectivity(_segment_2, ghost_type).begin(2);
			auto cend = this->mesh.getConnectivity(_segment_2, ghost_type).end(2);

			auto f_it = forces_internal_el.begin(2);

			auto strain_it = this->strains.begin();
			auto stress_it = this->stresses.begin();
			auto L_it = this->initial_lengths.begin();

			for (; cit != cend; ++cit, ++f_it, ++strain_it, ++stress_it, ++L_it) {
			const auto & conn = *cit;
			UInt n1 = conn(0);
			UInt n2 = conn(1);

			Real u1 = this->displacement(n1, _x);
			Real u2 = this->displacement(n2, _x);

			strain_it = (u2 - u1) / L_it;
			stress_it = E *strain_it;
			Real f_n = A * *stress_it;
			Vector<Real> & f = *f_it;

			f(0) = -f_n;
			f(1) = f_n;
			}

			this->getDOFManager().assembleElementalArrayLocalArray(
			forces_internal_el, internal_forces, _segment_2, ghost_type);
			}

			Real getPotentialEnergy() {
			Real res = 0;

			if (not lumped) {
			res = this->mulVectMatVect(this->displacement, "K", this->displacement);
			} else {
			auto strain_it = this->strains.begin();
			auto stress_it = this->stresses.begin();
			auto strain_end = this->strains.end();
			auto L_it = this->initial_lengths.begin();

			for (; strain_it != strain_end; ++strain_it, ++stress_it, ++L_it) {
			res += strain_it stress_it A * *L_it;
			}

			mesh.getCommunicator().allReduce(res, SynchronizerOperation::_sum);
			}

			return res / 2.;
			}

			Real getKineticEnergy() {
			Real res = 0;
			if (not lumped) {
			res = this->mulVectMatVect(this->velocity, "M", this->velocity);
			} else {
			Array<Real> & m = dynamic_cast<SolverVectorDefault &>(
			this->getDOFManager().getLumpedMatrix("M"));
			auto it = velocity.begin();
			auto end = velocity.end();
			auto m_it = m.begin();

			for (UInt node = 0; it != end; ++it, ++m_it, ++node) {
			if (mesh.isLocalOrMasterNode(node))
			res += m_it it *it;
			}

			mesh.getCommunicator().allReduce(res, SynchronizerOperation::_sum);
			}

			return res / 2.;
			}

			Real getExternalWorkIncrement() {
			Real res = 0;

			auto it = velocity.begin();
			auto end = velocity.end();
			auto if_it = internal_forces.begin();
			auto ef_it = forces.begin();
			auto b_it = blocked.begin();

			for (UInt node = 0; it != end; ++it, ++if_it, ++ef_it, ++b_it, ++node) {
			if (mesh.isLocalOrMasterNode(node))
			res += (b_it ? -if_it : ef_it) *it;
			}

			mesh.getCommunicator().allReduce(res, SynchronizerOperation::_sum);

			return res * this->getTimeStep();
			}

			Real mulVectMatVect(const Array<Real> & x, const ID & A_id,
			const Array<Real> & y) {
			Array<Real> Ay(nb_dofs);
			this->getDOFManager().assembleMatMulVectToArray("disp", A_id, y, Ay);

			Real res = 0.;
			for (auto && data : zip(arange(nb_dofs), make_view(Ay), make_view(x))) {
			res += std::get<2>(data) * std::get<1>(data) *
			mesh.isLocalOrMasterNode(std::get<0>(data));
			}

			mesh.getCommunicator().allReduce(res, SynchronizerOperation::_sum);
			return res;
			}

			/* ------------------------------------------------------------------------ */
			UInt getNbData(const Array<Element> & elements,
			const SynchronizationTag &) const override {
			return elements.size() * sizeof(Real);
			}

			void packData(CommunicationBuffer & buffer, const Array<Element> & elements,
			const SynchronizationTag & tag) const override {
			if (tag == SynchronizationTag::_user_1) {
			for (const auto & el : elements) {
			buffer << this->stresses(el.element);
			}
			}
			}

			void unpackData(CommunicationBuffer & buffer, const Array<Element> & elements,
			const SynchronizationTag & tag) override {
			if (tag == SynchronizationTag::_user_1) {
			auto cit = this->mesh.getConnectivity(_segment_2, _ghost).begin(2);

			for (const auto & el : elements) {
			Real stress;
			buffer >> stress;

			Real f = A * stress;

			Vector<UInt> conn = cit[el.element];
			this->internal_forces(conn(0), _x) += -f;
			this->internal_forces(conn(1), _x) += f;
			}
			}
			}

			const Mesh & getMesh() const { return mesh; }

			UInt getSpatialDimension() const { return 1; }

			auto & getBlockedDOFs() { return blocked; }

			private:
			UInt nb_dofs;
			UInt nb_elements;

			bool lumped;

			bool is_stiffness_assembled{false};
			bool is_mass_assembled{false};
			bool is_lumped_mass_assembled{false};

			public:
			Real E, A, rho;

			Mesh & mesh;
			Array<Real> displacement;
			Array<Real> velocity;
			Array<Real> acceleration;
			Array<bool> blocked;
			Array<Real> forces;
			Array<Real> internal_forces;

			Array<Real> stresses;
			Array<Real> strains;

			Array<Real> initial_lengths;
			};

			#endif /* AKANTU_TEST_MODEL_SOLVER_MY_MODEL_HH_ */

			} // namespace akantu

rAKA/test/test_model/test_common/test_model_solver/test_model_solver_my_model.hhe5cfe0ce664abugfixes/Unexpected…

test_model_solver_my_model.hhView Options

rAKA/test/test_model/test_common/test_model_solver/test_model_solver_my_model.hh
e5cfe0ce664abugfixes/Unexpected…

test_model_solver_my_model.hh
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