Cantera  3.1.0a1
Loading...
Searching...
No Matches
AdaptivePreconditioner.cpp
Go to the documentation of this file.
1//! @file AdaptivePreconditioner.cpp
2
3// This file is part of Cantera. See License.txt in the top-level directory or
4// at https://cantera.org/license.txt for license and copyright information.
5
8
9namespace Cantera
10{
11
12AdaptivePreconditioner::AdaptivePreconditioner()
13{
14 setPreconditionerSide("right");
15}
16
17void AdaptivePreconditioner::setValue(size_t row, size_t col, double value)
18{
19 m_jac_trips.emplace_back(static_cast<int>(row), static_cast<int>(col), value);
20}
21
22void AdaptivePreconditioner::stateAdjustment(vector<double>& state) {
23 // Only keep positive composition based on given tol
24 for (size_t i = 0; i < state.size(); i++) {
25 state[i] = std::max(state[i], m_atol);
26 }
27}
28
29void AdaptivePreconditioner::initialize(size_t networkSize)
30{
31 // don't use legacy rate constants
33 // reset arrays in case of re-initialization
34 m_jac_trips.clear();
35 // set dimensions of preconditioner from network
36 m_dim = networkSize;
37 // reserve some space for vectors making up SparseMatrix
38 m_jac_trips.reserve(3 * networkSize);
39 // reserve space for preconditioner
41 // creating sparse identity matrix
42 m_identity.resize(m_dim, m_dim);
43 m_identity.setIdentity();
44 m_identity.makeCompressed();
45 // setting default ILUT parameters
46 if (m_drop_tol == 0) {
47 setIlutDropTol(1e-10);
48 }
49 if (m_drop_tol == 0) {
50 setIlutFillFactor(static_cast<int>(m_dim) / 4);
51 }
52 // update initialized status
53 m_init = true;
54}
55
56
58{
59 // make into preconditioner as P = (I - gamma * J_bar)
61 // compressing sparse matrix structure
62 m_precon_matrix.makeCompressed();
63 // analyze and factorize
65 // check for errors
66 if (m_solver.info() != Eigen::Success) {
67 throw CanteraError("AdaptivePreconditioner::setup",
68 "error code: {}", static_cast<int>(m_solver.info()));
69 }
70}
71
73{
74 // set precon to jacobian
75 m_precon_matrix.setFromTriplets(m_jac_trips.begin(), m_jac_trips.end());
76 // convert to preconditioner
78 // prune by threshold if desired
79 if (m_prune_precon) {
81 }
82}
83
85{
86 for (int k=0; k<m_precon_matrix.outerSize(); ++k) {
87 for (Eigen::SparseMatrix<double>::InnerIterator it(m_precon_matrix, k); it;
88 ++it) {
89 if (std::abs(it.value()) < m_threshold && it.row() != it.col()) {
90 it.valueRef() = 0;
91 }
92 }
93 }
94}
95
96void AdaptivePreconditioner::solve(const size_t stateSize, double* rhs_vector, double*
97 output)
98{
99 // creating vectors in the form of Ax=b
100 Eigen::Map<Eigen::VectorXd> bVector(rhs_vector, stateSize);
101 Eigen::Map<Eigen::VectorXd> xVector(output, stateSize);
102 // solve for xVector
103 xVector = m_solver.solve(bVector);
104 if (m_solver.info() != Eigen::Success) {
105 throw CanteraError("AdaptivePreconditioner::solve",
106 "error code: {}", static_cast<int>(m_solver.info()));
107 }
108}
109
111 std::stringstream ss;
112 Eigen::IOFormat HeavyFmt(Eigen::FullPrecision, 0, ", ", ";\n", "[", "]", "[", "]");
113 ss << Eigen::MatrixXd(m_precon_matrix).format(HeavyFmt);
114 writelog(ss.str());
115}
116
118 std::stringstream ss;
119 Eigen::SparseMatrix<double> jacobian(m_dim, m_dim);
120 jacobian.setFromTriplets(m_jac_trips.begin(), m_jac_trips.end());
121 ss << Eigen::MatrixXd(jacobian);
122 writelog(ss.str());
123}
124
125}
Declarations for the class AdaptivePreconditioner which is a child class of PreconditionerBase for pr...
Eigen::IncompleteLUT< double > m_solver
Solver used in solving the linear system.
void setIlutDropTol(double droptol)
Set drop tolerance for ILUT.
double m_drop_tol
ILUT drop tolerance.
void solve(const size_t stateSize, double *rhs_vector, double *output) override
Solve a linear system Ax=b where A is the preconditioner.
void setValue(size_t row, size_t col, double value) override
Set a value at the specified row and column of the jacobian triplet vector.
double m_prune_precon
Bool set whether to prune the matrix or not.
double m_threshold
Minimum value a non-diagonal element must be to be included in the preconditioner.
void initialize(size_t networkSize) override
Called during setup for any processes that need to be completed prior to setup functions used in sund...
vector< Eigen::Triplet< double > > m_jac_trips
Vector of triples representing the jacobian used in preconditioning.
void setIlutFillFactor(int fillFactor)
Set the fill factor for ILUT solver.
Eigen::SparseMatrix< double > m_identity
Storage of appropriately sized identity matrix for making the preconditioner.
void printPreconditioner() override
Print preconditioner contents.
void setup() override
Perform preconditioner specific post-reactor setup operations such as factorize.
void stateAdjustment(vector< double > &state) override
Adjust the state vector based on the preconditioner, e.g., Adaptive preconditioning uses a strictly p...
void updatePreconditioner() override
Transform Jacobian vector and write into preconditioner, P = (I - gamma * J)
void prunePreconditioner()
Prune preconditioner elements.
void printJacobian()
Print jacobian contents.
Eigen::SparseMatrix< double > m_precon_matrix
Container that is the sparse preconditioner.
Base class for exceptions thrown by Cantera classes.
size_t m_dim
Dimension of the preconditioner.
double m_gamma
gamma value used in M = I - gamma*J
bool m_init
bool saying whether or not the preconditioner is initialized
double m_atol
Absolute tolerance of the ODE solver.
This file contains definitions for utility functions and text for modules, inputfiles and logging,...
Eigen::SparseMatrix< double > jacobian()
Return semi-analytical Jacobian of an AdaptivePreconditioner object.
void use_legacy_rate_constants(bool legacy)
Set definition used for rate constant calculation.
Definition global.cpp:102
void writelog(const string &fmt, const Args &... args)
Write a formatted message to the screen.
Definition global.h:175
Namespace for the Cantera kernel.
Definition AnyMap.cpp:564