Cantera 2.6.0

MultiJac.cpp
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1//! @file MultiJac.cpp Implementation file for class MultiJac
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
6#include "cantera/oneD/MultiJac.h"
7#include <ctime>
8
9 using namespace std;
10
11 namespace Cantera
12{
13
14MultiJac::MultiJac(OneDim& r)
15 : BandMatrix(r.size(),r.bandwidth(),r.bandwidth())
16{
17 m_size = r.size();
18 m_points = r.points();
19 m_resid = &r;
20 m_r1.resize(m_size);
21 m_ssdiag.resize(m_size);
22 m_mask.resize(m_size);
23 m_elapsed = 0.0;
24 m_nevals = 0;
25 m_age = 100000;
26 m_atol = sqrt(std::numeric_limits<double>::epsilon());
27 m_rtol = 1.0e-5;
28}
29
30 void MultiJac::updateTransient(doublereal rdt, integer* mask)
31{
32 for (size_t n = 0; n < m_size; n++) {
33 value(n,n) = m_ssdiag[n] - mask[n]*rdt;
34 }
35}
36
37 void MultiJac::incrementDiagonal(int j, doublereal d)
38{
39 m_ssdiag[j] += d;
40 value(j,j) = m_ssdiag[j];
41}
42
43 void MultiJac::eval(doublereal* x0, doublereal* resid0, doublereal rdt)
44{
45 m_nevals++;
46 clock_t t0 = clock();
47 bfill(0.0);
48 size_t ipt=0;
49
50 for (size_t j = 0; j < m_points; j++) {
51 size_t nv = m_resid->nVars(j);
52 for (size_t n = 0; n < nv; n++) {
53 // perturb x(n); preserve sign(x(n))
54 double xsave = x0[ipt];
55 double dx;
56 if (xsave >= 0) {
57 dx = xsave*m_rtol + m_atol;
58 } else {
59 dx = xsave*m_rtol - m_atol;
60 }
61 x0[ipt] = xsave + dx;
62 dx = x0[ipt] - xsave;
63 double rdx = 1.0/dx;
64
65 // calculate perturbed residual
66 m_resid->eval(j, x0, m_r1.data(), rdt, 0);
67
68 // compute nth column of Jacobian
69 for (size_t i = j - 1; i != j+2; i++) {
70 if (i != npos && i < m_points) {
71 size_t mv = m_resid->nVars(i);
72 size_t iloc = m_resid->loc(i);
73 for (size_t m = 0; m < mv; m++) {
74 value(m+iloc,ipt) = (m_r1[m+iloc] - resid0[m+iloc])*rdx;
75 }
76 }
77 }
78 x0[ipt] = xsave;
79 ipt++;
80 }
81 }
82
83 for (size_t n = 0; n < m_size; n++) {
84 m_ssdiag[n] = value(n,n);
85 }
86
87 m_elapsed += double(clock() - t0)/CLOCKS_PER_SEC;
88 m_age = 0;
89}
90
91} // namespace
MultiJac.h
Cantera
Namespace for the Cantera kernel.
Definition: AnyMap.cpp:557
Cantera::npos
const size_t npos
index returned by functions to indicate "no position"
Definition: ct_defs.h:192