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#include <iostream>
#include <cstdlib>
#include <utility>
#include <boost/numeric/ublas/vector.hpp>
#include <boost/numeric/ublas/matrix_sparse.hpp>
#include <amgcl/amg.hpp>
#include <amgcl/make_solver.hpp>
#include <amgcl/backend/builtin.hpp>
#include <amgcl/adapter/ublas.hpp>
#include <amgcl/coarsening/smoothed_aggregation.hpp>
#include <amgcl/relaxation/spai0.hpp>
#include <amgcl/solver/bicgstabl.hpp>
#include <amgcl/profiler.hpp>
#include "sample_problem.hpp"
typedef boost::numeric::ublas::compressed_matrix<
double, boost::numeric::ublas::row_major
> ublas_matrix;
typedef boost::numeric::ublas::vector<double> ublas_vector;
namespace amgcl {
profiler<> prof;
}
int main(int argc, char *argv[]) {
using amgcl::prof;
std::vector<int> ptr;
std::vector<int> col;
std::vector<double> val;
std::vector<double> rhs;
prof.tic("assemble");
int m = argc > 1 ? atoi(argv[1]) : 128;
int n = sample_problem(m, val, col, ptr, rhs);
// Create ublas matrix with the data.
ublas_matrix A(n, n);
A.reserve(ptr[n]);
for(int i = 0; i < n; ++i)
for(int j = ptr[i], e = ptr[i+1]; j < e; ++j)
A.push_back(i, col[j], val[j]);
prof.toc("assemble");
prof.tic("build");
amgcl::make_solver<
amgcl::amg<
amgcl::backend::builtin<double>,
amgcl::coarsening::smoothed_aggregation,
amgcl::relaxation::spai0
>,
amgcl::solver::bicgstabl<
amgcl::backend::builtin<double>
>
> solve( amgcl::backend::map(A) );
prof.toc("build");
std::cout << solve.precond() << std::endl;
ublas_vector x(n, 0);
prof.tic("solve");
size_t iters;
double resid;
std::tie(iters, resid) = solve(rhs, x);
prof.toc("solve");
std::cout << "Iterations: " << iters << std::endl
<< "Error: " << resid << std::endl
<< std::endl << prof << std::endl;
}
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