Adds an extra program option: the random seed (optional)

lib/splitting_tree.cpp

@@ -15,7 +15,7 @@ splitting_tree::splitting_tree(size_t N, size_t d) : states(N), depth(d) {
 	iota(begin(states), end(states), 0);
 }
 
-result create_splitting_tree(const mealy & g, options opt) {
+result create_splitting_tree(const mealy & g, options opt, uint_fast32_t random_seed) {
 	const auto N = g.graph_size;
 	const auto P = g.input_size;
 	const auto Q = g.output_size;
@@ -34,8 +34,7 @@ result create_splitting_tree(const mealy & g, options opt) {
 	// List of inputs, will be shuffled in case of randomizations
 	vector<input> all_inputs(P);
 	iota(begin(all_inputs), end(all_inputs), 0);
-	random_device rd;
+	mt19937 generator(random_seed);
-	mt19937 generator(rd());
 
 	size_t current_order = 0;
 	bool split_in_current_order = false;

lib/splitting_tree.hpp

@@ -111,4 +111,4 @@ struct result {
 
 /// \brief Creates a splitting tree by partition refinement.
 /// \returns a splitting tree and other calculated structures.
-result create_splitting_tree(mealy const & m, options opt);
+result create_splitting_tree(mealy const & m, options opt, uint_fast32_t random_seed);

lib/test_suite.cpp

@@ -34,11 +34,10 @@ void test(const mealy & specification, const transfer_sequences & prefixes,
 
 void randomized_test(const mealy & specification, const transfer_sequences & prefixes,
                      const separating_family & separating_family, size_t min_k, size_t rnd_length,
-                     const writer & output) {
+                     const writer & output, uint_fast32_t random_seed) {
 	clog << "*** K >= " << min_k << endl;
 
-	std::random_device rd;
+	std::mt19937 generator(random_seed);
-	std::mt19937 generator(rd());
 
 	// https://en.wikipedia.org/wiki/Geometric_distribution we have the random variable Y here
 	uniform_int_distribution<> unfair_coin(0, rnd_length);

lib/test_suite.hpp

@@ -19,7 +19,7 @@ void test(mealy const & specification, transfer_sequences const & prefixes,
 /// \brief Performs random non-exhaustive tests for more states (harmonized, e.g. HSI / DS)
 void randomized_test(mealy const & specification, transfer_sequences const & prefixes,
                                   separating_family const & separating_family, size_t min_k,
-                                  size_t rnd_length, writer const & output);
+                                  size_t rnd_length, writer const & output, uint_fast32_t random_seed);
 
 /// \brief returns a writer which simply writes everything to cout (via inputs)
 writer default_writer(const std::vector<std::string> & inputs);

lib/transfer_sequences.cpp

@@ -38,9 +38,8 @@ transfer_sequences create_transfer_sequences(const mealy& machine, state s){
 	return words;
 }
 
-transfer_sequences create_randomized_transfer_sequences(const mealy & machine, state s){
+transfer_sequences create_randomized_transfer_sequences(const mealy & machine, state s, uint_fast32_t random_seed){
-	random_device rd;
+	mt19937 generator(random_seed);
-	mt19937 generator(rd());
 
 	vector<bool> visited(machine.graph_size, false);
 	vector<word> words(machine.graph_size);

lib/transfer_sequences.hpp

@@ -7,4 +7,4 @@ struct mealy;
 using transfer_sequences = std::vector<word>;
 
 transfer_sequences create_transfer_sequences(mealy const & machine, state s);
-transfer_sequences create_randomized_transfer_sequences(mealy const & machine, state s);
+transfer_sequences create_randomized_transfer_sequences(mealy const & machine, state s, uint_fast32_t random_seed);

src/main.cpp

@@ -18,8 +18,8 @@ using namespace std;
 using time_logger = silent_timer;
 
 int main(int argc, char *argv[]) try {
-	if(argc != 5) {
+	if(argc != 5 && argc != 6) {
-		cerr << "usage: main <filename> <max k> <rnd length> <all|fixed|random>" << endl;
+		cerr << "usage: main <filename> <max k> <rnd length> <all|fixed|random> [<seed>]" << endl;
 		return 1;
 	}
 	const string filename = argv[1];
@@ -32,6 +32,9 @@ int main(int argc, char *argv[]) try {
 	const bool streaming = mode == "all" || mode == "fixed";
 	const bool random_part = mode == "all" || mode == "random";
 
+	const bool seed_provided = argc == 6;
+	const uint_fast32_t seed = seed_provided ? stoul(argv[5]) : 0;
+
 	const bool use_distinguishing_sequence = true;
 	const bool randomize_prefixes = true;
 	const bool randomize_hopcroft = true;
@@ -57,10 +60,23 @@ int main(int argc, char *argv[]) try {
 	const auto & machine = reachable_submachine(move(machine_and_translation.first), 0);
 	const auto & translation = machine_and_translation.second;
 
+	// every thread gets its own seed
+	const auto random_seeds = [&] {
+		vector<uint_fast32_t> seeds(4);
+		if (seed_provided) {
+			seed_seq s{seed};
+			s.generate(seeds.begin(), seeds.end());
+		} else {
+			random_device rd;
+			generate(seeds.begin(), seeds.end(), ref(rd));
+		}
+		return seeds;
+	}();
+
 	auto all_pair_separating_sequences = [&]{
 		const auto splitting_tree_hopcroft = [&]{
 			time_logger t("creating hopcroft splitting tree");
-			return create_splitting_tree(machine, randomize_hopcroft ? randomized_hopcroft_style : hopcroft_style);
+			return create_splitting_tree(machine, randomize_hopcroft ? randomized_hopcroft_style : hopcroft_style, random_seeds[0]);
 		}();
 
 		return splitting_tree_hopcroft.root;
@@ -70,7 +86,7 @@ int main(int argc, char *argv[]) try {
 		const auto tree = [&]{
 			time_logger t("Lee & Yannakakis I");
 			if(use_distinguishing_sequence)
-				return create_splitting_tree(machine, randomize_lee_yannakakis ? randomized_lee_yannakakis_style : lee_yannakakis_style);
+				return create_splitting_tree(machine, randomize_lee_yannakakis ? randomized_lee_yannakakis_style : lee_yannakakis_style, random_seeds[1]);
 			else
 				return result(machine.graph_size);
 		}();
@@ -86,7 +102,7 @@ int main(int argc, char *argv[]) try {
 	auto transfer_sequences = [&]{
 		time_logger t("determining transfer sequences");
 		if(randomize_prefixes){
-			return create_randomized_transfer_sequences(machine, 0);
+			return create_randomized_transfer_sequences(machine, 0, random_seeds[2]);
 		} else {
 			return create_transfer_sequences(machine, 0);
 		}
@@ -107,7 +123,7 @@ int main(int argc, char *argv[]) try {
 	if(random_part){
 		time_logger t("outputting all random tests");
 		const auto k_max_ = streaming ? k_max + 1 : 0;
-		randomized_test(machine, transfer_sequences, separating_family, k_max_, rnd_length, default_writer(inputs));
+		randomized_test(machine, transfer_sequences, separating_family, k_max_, rnd_length, default_writer(inputs), random_seeds[3]);
 	}
 
 } catch (exception const & e) {

src/methods.cpp

@@ -6,8 +6,9 @@
 #include <trie.hpp>
 
 #include <future>
-#include <string>
 #include <iostream>
+#include <random>
+#include <string>
 
 using namespace std;
 
@@ -23,14 +24,16 @@ static Method parse_method(string const & s) {
 }
 
 int main(int argc, char * argv[]) {
-	if (argc != 4) {
+	if (argc != 4 && argc != 5) {
-		cerr << "usage: methods <file> <mode> <k_max>\n";
+		cerr << "usage: methods <file> <mode> <k_max> [<seed>]\n";
 		return 1;
 	}
 
 	const string filename = argv[1];
 	const Method method = parse_method(argv[2]);
 	const size_t k_max = std::stoul(argv[3]);
+	const bool seed_provided = argc == 5;
+	const uint_fast32_t seed = seed_provided ? stoul(argv[5]) : 0;
 
 	const auto machine = [&] {
 		if (filename.find(".txt") != string::npos) {
@@ -43,21 +46,33 @@ int main(int argc, char * argv[]) {
 		return read_mealy_from_dot(filename).first;
 	}();
 
+	const auto random_seeds = [&] {
+		vector<uint_fast32_t> seeds(3);
+		if (seed_provided) {
+			seed_seq s{seed};
+			s.generate(seeds.begin(), seeds.end());
+		} else {
+			random_device rd;
+			generate(seeds.begin(), seeds.end(), ref(rd));
+		}
+		return seeds;
+	}();
+
 	auto sequence_fut = async([&] {
 		if (method == hsi_method) {
 			return create_adaptive_distinguishing_sequence(result(machine.graph_size));
 		}
-		const auto tree = create_splitting_tree(machine, randomized_lee_yannakakis_style);
+		const auto tree = create_splitting_tree(machine, randomized_lee_yannakakis_style, random_seeds[0]);
 		return create_adaptive_distinguishing_sequence(tree);
 	});
 
 	auto pairs_fut = async([&] {
-		const auto tree = create_splitting_tree(machine, randomized_min_hopcroft_style);
+		const auto tree = create_splitting_tree(machine, randomized_min_hopcroft_style, random_seeds[1]);
 		return tree.root;
 	});
 
 	auto prefixes_fut = async([&] {
-		return create_transfer_sequences(machine, 0);
+		return create_randomized_transfer_sequences(machine, 0, random_seeds[2]);
 	});
 
 	auto middles_fut = async([&] {

src/trees.cpp

@@ -3,8 +3,9 @@
 #include <splitting_tree.hpp>
 #include <write_tree_to_dot.hpp>
 
-#include <string>
 #include <iostream>
+#include <random>
+#include <string>
 
 using namespace std;
 
@@ -20,7 +21,9 @@ int main(int argc, char * argv[]) {
 	const auto & translation = machine_and_translation.second;
 
 	const auto options = randomized ? randomized_lee_yannakakis_style : lee_yannakakis_style;
-	const auto tree = create_splitting_tree(machine, options);
+
+	random_device rd;
+	const auto tree = create_splitting_tree(machine, options, rd());
 	const auto sequence = create_adaptive_distinguishing_sequence(tree);
 
 	write_splitting_tree_to_dot(tree.root, filename + ".tree");