Work in progress on AnisotropicEikonal.

This commit is contained in:
Atgeirr Flø Rasmussen 2014-11-21 15:06:37 +01:00
parent 84da6a28f3
commit ee4d2be67e
2 changed files with 121 additions and 3 deletions

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@ -20,6 +20,7 @@
#include <opm/core/tof/AnisotropicEikonal.hpp>
#include <opm/core/grid/GridUtilities.hpp>
#include <opm/core/grid.h>
#include <set>
namespace Opm
{
@ -34,6 +35,7 @@ namespace Opm
}
cell_neighbours_ = vertexNeighbours(grid);
orderCounterClockwise(grid, cell_neighbours_);
considered_.reserve(100);
}
/// Solve the eikonal equation.
@ -42,12 +44,119 @@ namespace Opm
/// \param[out] solution Array of solution to the eikonal equation.
void AnisotropicEikonal2d::solve(const double* metric,
const std::vector<int>& startcells,
std::vector<double>& solution) const
std::vector<double>& solution)
{
// The algorithm used is described in J.A. Sethian and A. Vladimirsky,
// "Ordered Upwind Methods for Static Hamilton-Jacobi Equations".
// Notation in comments is as used in that paper: U is the solution,
// and q is the boundary condition. One difference is that we talk about
// grid cells instead of mesh points.
//
// Algorithm summary:
// 1. Put all cells in Far. U_i = \inf.
// 2. Move the startcells to Accepted. U_i = q(x_i)
// 3. Move cells adjacent to startcells to Considered, evaluate
// U_i = min_{(x_j,x_k) \in NF(x_i)} G_{j,k}
// 4. Find the Considered cell with the smallest value: r.
// 5. Move cell r to Accepted. Update AcceptedFront.
// 6. Move cells adjacent to r from Far to Considered.
// 7. Recompute the value for all Considered cells within
// distance h * F_2/F1 from x_r. Use min of previous and new.
// 8. If Considered is not empty, go to step 4.
// 1. Put all cells in Far. U_i = \inf.
const int num_cells = grid_.number_of_cells;
const double inf = 1e100;
solution.clear();
solution.resize(num_cells, inf);
considered_.clear();
is_considered_.clear();
is_considered_.resize(num_cells, false);
// 2. Move the startcells to Accepted. U_i = q(x_i)
std::vector<char> accepted(num_cells, false);
const int num_startcells = startcells.size();
for (int ii = 0; ii < num_startcells; ++ii) {
accepted[startcells[ii]] = true;
solution[startcells[ii]] = 0.0;
}
std::set<int> accepted_front(startcells.begin(), startcells.end());
// 3. Move cells adjacent to startcells to Considered, evaluate
// U_i = min_{(x_j,x_k) \in NF(x_i)} G_{j,k}
for (int ii = 0; ii < num_startcells; ++ii) {
const int scell = startcells[ii];
const int num_nb = cell_neighbours_[scell].size();
for (int nb = 0; nb < num_nb; ++nb) {
const int nb_cell = cell_neighbours_[scell][nb];
if (!is_considered_[nb_cell]) {
const double value = computeValue(nb_cell);
pushConsidered(std::make_pair(value, nb_cell));
is_considered_[nb_cell] = true;
}
}
}
// 4. Find the Considered cell with the smallest value: r.
// 5. Move cell r to Accepted. Update AcceptedFront.
// 6. Move cells adjacent to r from Far to Considered.
// 7. Recompute the value for all Considered cells within
// distance h * F_2/F1 from x_r. Use min of previous and new.
// 8. If Considered is not empty, go to step 4.
// 1.
}
double AnisotropicEikonal2d::computeValue(const int cell) const
{
const auto& nbs = cell_neighbours_[cell];
const int num_nbs = nbs.size();
double val = 1e100;
for (int ii = 0; ii < num_nbs; ++ii) {
const int n[2] = { nbs[ii], nbs[(ii+1) % num_nbs] };
// if ... accepted front
}
return val;
}
const AnisotropicEikonal2d::ValueAndCell& AnisotropicEikonal2d::topConsidered() const
{
return considered_.front();
}
void AnisotropicEikonal2d::pushConsidered(const ValueAndCell& vc)
{
considered_.push_back(vc);
std::push_heap(considered_.begin(), considered_.end());
}
void AnisotropicEikonal2d::popConsidered()
{
std::pop_heap(considered_.begin(), considered_.end());
considered_.pop_back();
}
} // namespace Opm

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@ -45,10 +45,19 @@ namespace Opm
/// \param[out] solution Array of solution to the eikonal equation.
void solve(const double* metric,
const std::vector<int>& startcells,
std::vector<double>& solution) const;
std::vector<double>& solution);
private:
const UnstructuredGrid& grid_;
SparseTable<int> cell_neighbours_;
typedef std::pair<double, int> ValueAndCell;
std::vector<ValueAndCell> considered_;
std::vector<char> is_considered_;
double computeValue(const int cell) const;
const ValueAndCell& topConsidered() const;
void pushConsidered(const ValueAndCell& vc);
void popConsidered();
};
} // namespace Opm