Read and write graph and batch files

The readers and writers are in dyng::io (<dyng/dyng.hpp> includes them). Every reader validates its input and throws dyng::io_error with the path, line and column of the problem; the formats are specified in File formats.

A graph in MOSP’s text CSR format

using vertex = std::int32_t; using edge = std::int32_t; using weight = std::int32_t;
auto csr = dyng::io::read_csr_triplet<vertex, edge, weight>("data/graphCsr");  // RowPtr/ColInd/Values
auto g = dyng::graph<vertex, edge, weight>::from_csr(res, csr.view(),
                                                     dyng::graph_properties::mosp_compatible());

graph_properties::mosp_compatible() reproduces how the original applies batches (append row order, parallel edges and self-loops kept); without it the graph uses dynG’s defaults (ADR 0010).

A Matrix Market file

dyng::io::matrix_market_options options;   // weights: from the file, or seeded random weights
auto edges = dyng::io::read_matrix_market<vertex, weight>("roadNet-CA.mtx", options);
auto g = dyng::graph<vertex, edge, weight>::from_edges(res, edges.view());

With options.weights = dyng::io::matrix_market_weights::random and the default random_weights, the edges, their order and their weights are bit-identical to mospPrep mtx2csr <in.mtx> <prefix> K 1 100 12345 of the original tools.

A batch

dyng::io::legacy_batch_options bopts;
bopts.num_weights = g.num_weights();
bopts.num_vertices = g.num_vertices();      // ids are checked against it
auto batch = dyng::io::read_legacy_batch<vertex, weight>("insert.txt", "delete.txt", bopts);
dyng::sssp::update(res, g, batch.view(), tree);

A sequence of batches in the library’s text format (.dgt, File formats):

dyng::io::batch_file_options fopts;
fopts.num_vertices = g.num_vertices();
for (const auto& b : dyng::io::read_batches<vertex, weight>("stream.dgt", fopts)) {
  dyng::sssp::update(res, g, b.view(), tree);
}

Results

dyng::io::write_distances("out/distances.txt", tree.distances());
dyng::io::write_parents("out/SSSPTree.txt", tree.parents());

The writers produce the same bytes as the original tools, which is what the parity harness compares (Run the parity check).