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runVelIC

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This commit is contained in:
Aik-Siong Koh
2023-06-18 01:06:39 -06:00
parent 3b08cd72df
commit 371b13a9e0
147 changed files with 2555 additions and 238 deletions
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27
MbDCode/StableBackwardDifference.cpp
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@@ -1,5 +1,7 @@
#include "StableBackwardDifference.h"
using namespace MbD;
void MbD::StableBackwardDifference::formTaylorMatrix()
{
//This form is numerically more stable and is prefered over the full Taylor Matrix.
@@ -8,21 +10,38 @@ void MbD::StableBackwardDifference::formTaylorMatrix()
//| (t2 - t) (t2 - t) ^ 2 / 2! (t2 - t) ^ 3 / 3!| |qdd(t) | |q(t2) - q(t) |
//| (t3 - t) (t3 - t) ^ 2 / 2! (t3 - t) ^ 3 / 3!| |qddd(t)| |q(t3) - q(t) |
this->instanciateTaylorMatrix();
this->instantiateTaylorMatrix();
for (int i = 0; i < order; i++)
{
this->formTaylorRowwithTimeNodederivative(i, i, 0);
}
}
void MbD::StableBackwardDifference::instanciateTaylorMatrix()
void MbD::StableBackwardDifference::instantiateTaylorMatrix()
{
if (taylorMatrix->empty() || (taylorMatrix->nrow() != (order))) {
if (taylorMatrix == nullptr || (taylorMatrix->nrow() != (order))) {
taylorMatrix = std::make_shared<FullMatrix<double>>(order, order);
}
}
void MbD::StableBackwardDifference::formTaylorRowwithTimeNodederivative(int i, int ii, int k)
{
assert(false);
//| rowi hi hipower aij |
auto& rowi = taylorMatrix->at(i);
if (k > 0) {
for (int j = 0; j < k - 1; j++)
{
rowi->at(j) = 0.0;
}
rowi->at(k) = 1.0;
}
auto hi = timeNodes->at(ii) - time;
auto hipower = 1.0;
for (int j = k; j < order; j++)
{
hipower *= hi;
auto aij = hipower * OneOverFactorials->at((size_t)(j - k));
rowi->at(j) = aij;
}
}