int main(int argc, char *argv[])
{
if (argc < 3) {
std::cout << "Usage: " << argv[0] << " input-matrix output-matrix" << std::endl;
return 1;
}
std::string fname_mat (argv[1]);
bool verbose (true);
// *** reading matrix in crs format from file
std::ifstream in(fname_mat.c_str(), std::ios::in | std::ios::binary);
double *A(NULL);
unsigned *iA(NULL), *jA(NULL), n;
if (in) {
if (verbose) {
std::cout << "reading matrix from " << fname_mat << " ... " << std::flush;
}
BaseLib::RunTime timer;
timer.start();
CS_read(in, n, iA, jA, A);
in.close();
timer.stop();
if (verbose) {
std::cout << "ok, " << timer.elapsed() << " s" << std::endl;
}
} else {
std::cout << "error reading matrix from " << fname_mat << std::endl;
}
unsigned nnz(iA[n]);
if (verbose) {
std::cout << "Parameters read: n=" << n << ", nnz=" << nnz << std::endl;
}
MathLib::CRSMatrix<double, unsigned> *mat (new MathLib::CRSMatrix<double, unsigned>(n, iA, jA, A));
const unsigned n_rows_cols_to_erase(300);
unsigned *rows_cols_to_erase(new unsigned[n_rows_cols_to_erase]);
for (unsigned k(0); k<n_rows_cols_to_erase; k++) {
rows_cols_to_erase[k] = (k+1)*2;
}
BaseLib::RunTime timer;
std::cout << "erasing " << n_rows_cols_to_erase << " rows and columns ... " << std::flush;
timer.start();
mat->eraseEntries(n_rows_cols_to_erase, rows_cols_to_erase);
timer.stop();
std::cout << "ok, " << timer.elapsed() << " s" << std::endl;
delete[] rows_cols_to_erase;
fname_mat = argv[2];
std::ofstream out (fname_mat.c_str(), std::ios::binary);
CS_write (out, mat->getNRows(), mat->getRowPtrArray(), mat->getColIdxArray(), mat->getEntryArray());
out.close();
std::cout << "wrote " << fname_mat << " with " << mat->getNRows() << " rows and " << mat->getRowPtrArray()[mat->getNRows()] << " entries" << std::endl;
delete mat;
}
