void pretty_print_matrix(std::ostream &ostr, MatrixT const &mat)
{
IndexType rows, cols;
mat.get_shape(rows, cols);
typename MatrixT::ScalarType zero(mat.get_zero());
for (IndexType row = 0; row < rows; ++row)
{
ostr << ((row == 0) ? "[[" : " [");
if (cols > 0)
{
auto val = mat.get_value_at(row, 0);
if (val == zero)
ostr << " ";
else
ostr << val;
}
for (IndexType col = 1; col < cols; ++col)
{
auto val = mat.get_value_at(row, col);
if (val == zero)
ostr << ", ";
else
ostr << ", " << val;
}
ostr << ((row == rows - 1) ? "]]\n" : "]\n");
}
}
static void discharge(MatrixT const &C,
MatrixT &F,
MatrixT &excess,
MatrixT &height,
MatrixT &seen,
graphblas::IndexType u)
{
graphblas::IndexType num_nodes, cols;
C.get_shape(num_nodes, cols);
while (excess.get_value_at(0, u) > 0)
{
if (seen.get_value_at(0, u) < num_nodes)
{
graphblas::IndexType v = seen.get_value_at(0, u);
if (((C.get_value_at(u, v) - F.get_value_at(u, v)) > 0) &&
(height.get_value_at(0, u) > height.get_value_at(0, v)))
{
push(C, F, excess, u, v);
}
else
{
seen.set_value_at(0, u, seen.get_value_at(0, u) + 1);
}
}
else
{
relabel(C, F, height, u);
seen.set_value_at(0, u, 0);
}
}
}
static void push(MatrixT const &C,
MatrixT &F,
MatrixT &excess,
graphblas::IndexType u,
graphblas::IndexType v)
{
using T = typename MatrixT::ScalarType;
T a = excess.get_value_at(0, u);
T b = C.get_value_at(u, v) - F.get_value_at(u, v);
T send = std::min(a, b);
F.set_value_at(u, v, F.get_value_at(u, v) + send);
F.set_value_at(v, u, F.get_value_at(v, u) - send);
excess.set_value_at(0, u, excess.get_value_at(0, u) - send);
excess.set_value_at(0, v, excess.get_value_at(0, v) + send);
}
static void relabel(MatrixT const &C,
MatrixT const &F,
MatrixT &height,
graphblas::IndexType u)
{
using T = typename MatrixT::ScalarType;
graphblas::IndexType num_nodes, cols;
C.get_shape(num_nodes, cols);
T min_height = std::numeric_limits<T>::max();
for (graphblas::IndexType v = 0; v < num_nodes; ++v)
{
if ((C.get_value_at(u, v) - F.get_value_at(u, v)) > 0)
{
T a = height.get_value_at(0, v);
min_height = std::min(min_height, a);
height.set_value_at(0, u, min_height + 1);
}
}
}
void row_index_of(MatrixT &mat)
{
graphblas::IndexType rows, cols;
mat.get_shape(rows, cols);
for (IndexType i = 0; i < rows; ++i)
{
for (IndexType j = 0; j < cols; ++j)
{
auto mat_ij = mat.get_value_at(i, j);
if (mat_ij != mat.get_zero())
{
mat.set_value_at(i, j, i);
}
}
}
}