Ejemplo n.º 1
0
    def _solve_instance(self,
                        algo,
                        pfn,
                        round_D_func=None,
                        require_K=False,
                        predefined_k=None,
                        suppress_constraint_check=False):
        N, points, dd_points, d, D, C, _ = cvrp_io.read_TSPLIB_CVRP(pfn)
        K, L, service_time = cvrp_io.read_TSBLIB_additional_constraints(pfn)

        if round_D_func:
            D = round_D_func(D)

        if predefined_k is not None:
            K = predefined_k
        if require_K and (K is None):
            raise IOError(
                "It is required that the VEHICLE field is set in %s" % pfn)

        if service_time:
            half_st = service_time / 2.0
            if int(half_st) == half_st:
                half_st = int(half_st)
                service_time = int(service_time)

            # The service time can be modeled modifying the distance
            #  matrix in a way that any visit to a depot node costs
            #  service_time units.
            D_c = np.copy(D)
            D_c[1:, 1:] += service_time
            D_c[0, :] += half_st
            D_c[:, 0] += half_st
            np.fill_diagonal(D_c, 0.0)
        else:
            D_c = D

        if points is None and dd_points is not None:
            points = dd_points

        startt = time()
        if require_K:
            sol = algo(points, D_c, d, C, L, service_time, K)
        else:
            sol = algo(points, D_c, d, C, L, service_time)
        endt = time()
        elapsedt = endt - startt

        if __debug__:
            print_solution_statistics(sol, D, D_c, d, C, L, service_time)

        cover_ok, capa_ok, rlen_ok = check_solution_feasibility(
            sol, D, d, C, L, True)
        if not suppress_constraint_check:
            self.assertTrue(cover_ok, "Must be a valid solution")
            self.assertTrue(capa_ok, "Must not violate the C constraint")
            self.assertTrue(rlen_ok, "Must not violate the L constraint")

        return sol, objf(sol, D), objf(sol, D_c), elapsedt
 def test_improve_eil101_solution(self):
     # only test this on the first iteration
     global iteration
     if iteration>0:
         return
     
     pp = os.path.join( BENCHMARKS_BASEPATH, "Classic",
                     "ChristofidesEilon1969","10-eil101.vrp")
     N, points, dd_points, d, D, C, _ = read_TSPLIB_CVRP( pp )
     sol = [0, 40, 21, 58, 13, 0, 70, 30, 20, 66, 71, 65, 35, 9, 81, 33, 78, 79, 3, 24, 55, 0, 82, 48, 47, 36, 49, 64, 63, 90, 11, 19, 62, 10, 0, 4, 25, 39, 67, 23, 56, 75, 41, 22, 74, 72, 73, 91, 0, 57, 42, 14, 38, 44, 16, 86, 17, 46, 61, 85, 98, 37, 92, 6, 0, 60, 26, 12, 54, 80, 68, 29, 34, 51, 1, 50, 77, 76, 28, 0, 94, 95, 97, 87, 2, 15, 43, 100, 93, 59, 99, 96, 7, 0, 27, 69, 31, 32, 88, 8, 45, 84, 5, 83, 18, 52, 89, 53, 0]
 
     _compare_improved_from_solution(
         self, sol, D,d,C,None,
         [do_relocate_move, do_1point_move], [do_naive_1point_move])
Ejemplo n.º 3
0
def tsp_cli(tsp_f_name, tsp_f):
    # import here so that the function can be used without these dependencies
    from util import objf
    
    if len(sys.argv)==2 and path.isfile(sys.argv[1]):
        P = cvrp_io.read_TSPLIB_CVRP(sys.argv[1])
        D = P.distance_matrix
        start_t = time()
        tsp_sol, tsp_f = tsp_f(D, list(range(len(D))))
        elapsed_t = time()-start_t
        print("Solved %s with %s in %.2f s"%(path.basename(sys.argv[1]), 
                                             tsp_f_name, elapsed_t))
        tsp_o = objf(tsp_sol,D)
        print("SOLUTION:", str(tsp_sol))
        print("COST:", tsp_o)  
        assert(tsp_f==tsp_o)
    else:
        print("usage: tsp_solver_%s.py TSPLIB_file.tsp"%tsp_f_name, file=sys.stderr)
Ejemplo n.º 4
0
    def test_verify_reference_solutions_FosterRyan1976_instances(self):
        for problem_idx, problem_name in enumerate(self.problem_names):
            ref_k, ref_f = self.targets[1][problem_idx]

            if problem_name == r"04-CW64_n30a_k8c.vrp":
                problem_name = r"04-CW64_n31_k9c.vrp"
                ref_f = 1377

            pfn = path.join(BENCHMARKS_BASEPATH, self.problem_path,
                            problem_name)
            N, points, dd_points, d, D, C, _ = cvrp_io.read_TSPLIB_CVRP(pfn)
            K, L, service_time = cvrp_io.read_TSBLIB_additional_constraints(
                pfn)
            if service_time:
                D_c = D2D_c(D, service_time)
            else:
                D_c = D

            ref_sol = self.target_solutions[problem_idx]
            ref_sol_f = int(objf(ref_sol, D_c))
            ref_sol_k = ref_sol.count(0) - 1

            cover_ok, capa_ok, rlen_ok = check_solution_feasibility(
                ref_sol, D, d, C, L, True)
            self.assertTrue(cover_ok, "Must be a valid solution")
            self.assertTrue(capa_ok, "Must not violate the C constraint")
            self.assertTrue(rlen_ok, "Must not violate the L constraint")

            self.assertEqual(
                ref_k,
                ref_sol_k,
                msg=
                ("The appendix solution route count differs from the one given "
                 + "in Table 2 for %s (%d vs %d)" %
                 (problem_name, ref_sol_k, ref_k)))
            self.assertAlmostEqual(
                ref_f,
                ref_sol_f,
                msg=("The appendix solution result differs from the one given "
                     + "in Table 2 for %s : %d (ours) vs %d (theirs)" %
                     (problem_name, ref_sol_f, ref_f)))
Ejemplo n.º 5
0
    def test_seed_point_gen_vs_fig4_example(self):
        pfn = r"fisher_jaikumar_fig4.vrp"
        seed_example_problem_instance = cvrp_io.read_TSPLIB_CVRP(pfn)
        seed_example_seed_points = _read_TSPLIB_seed_points(pfn)

        N, points, dd_points, d, D, C, _ = seed_example_problem_instance
        generated_seeds = _sweep_seed_points(points, D, d, C, 3)

        #ran = np.amax(points)-np.amin(points)
        #tol = ran*(RIGHT_SEED_POS_TOL/100.0)

        avg_rel_d = 0.0
        for gx, gy in generated_seeds:
            # find the closest match
            min_d = None
            min_idx = None
            for ri, (rx, ry) in enumerate(seed_example_seed_points):

                dd = sqrt((points[0][0] - rx)**2 + (points[0][1] - ry)**2)
                tol = dd * (RIGHT_SEED_POS_TOL / 100.0)

                d = sqrt((gx - rx)**2 + (gy - ry)**2)
                avg_rel_d += d / dd
                if (min_d is None) or (d < min_d):
                    min_d = d
                    min_idx = ri

            #print min_d, tol
            self.assertAlmostEqual(
                min_d,
                0.0,
                delta=tol,
                msg="The seed point %d is over %.2f %% off" %
                (min_idx + 1, RIGHT_SEED_POS_TOL))
        avg_rel_d = avg_rel_d / len(generated_seeds)
        print(avg_rel_d)
Ejemplo n.º 6
0
def read_and_solve_a_problem(problem_instance_path,
                             with_algorithm_function,
                             minimize_K,
                             best_of_n=1,
                             verbosity=-1,
                             single=False,
                             measure_time=False):
    """ Solve a problem instance with the path in problem_instance_path
    with the agorithm in <with_algorithm_function>.
    
    The <with_algorithm_function> has a signature of:
    init_f(points, D_c, d, C, L, st, wtt, verbosity, single, minimize_K)
    
    Options <verbosity>, <single> and <measure_time> may be used to adjust what
    is printed and if a restricted single iteration search (different meaning 
    for different algorithms) is made."""

    pfn = problem_instance_path
    N, points, dd_points, d, D, C, ewt = cvrp_io.read_TSPLIB_CVRP(pfn)
    required_K, L, st = cvrp_io.read_TSBLIB_additional_constraints(pfn)

    # model service time with the distance matrix
    D_c = cvrp_ops.D2D_c(D, st) if st else D

    if points is None:
        if dd_points is not None:
            points = dd_points
        else:
            points, ewt = cvrp_ops.generate_missing_coordinates(D)

    tightness = None
    if C and required_K:
        tightness = (sum(d) / (C * required_K))
    if verbosity >= 0:
        print_problem_information(points, D, d, C, L, st, tightness, verbosity)

    best_sol = None
    best_f = float('inf')
    best_K = len(D)
    interrupted = False
    for repeat_n in range(best_of_n):

        sol, sol_f, sol_K = None, float('inf'), float('inf')
        start = time()
        try:
            sol = with_algorithm_function(points, D_c, d, C, L, st, ewt,
                                          single, minimize_K)
        except KeyboardInterrupt as e:
            print("WARNING: Solving was interrupted, returning " +
                  "intermediate solution",
                  file=sys.stderr)
            interrupted = True
            # if interrupted on initial sol gen, return the best of those
            if len(e.args) > 0 and type(e.args[0]) is list:
                sol = e.args[0]
        elapsed = time() - start

        if sol:
            sol = cvrp_ops.normalize_solution(sol)
            sol_f = objf(sol, D_c)
            sol_K = sol.count(0) - 1
            if is_better_sol(best_f, best_K, sol_f, sol_K, minimize_K):
                best_sol = sol
                best_f = sol_f
                best_K = sol_K
            if best_of_n > 1 and verbosity >= 1:
                print("SOLUTION QUALITY %d of %d: %.2f" %
                      (repeat_n + 1, best_of_n, objf(best_sol, D_c)))
            if measure_time or verbosity >= 1:
                print("SOLVED IN: %.2f s" % elapsed)

        if interrupted:
            break

    if verbosity >= 0 and best_sol:
        n_best_sol = cvrp_ops.normalize_solution(best_sol)
        print_solution_statistics(n_best_sol,
                                  D,
                                  D_c,
                                  d,
                                  C,
                                  L,
                                  st,
                                  verbosity=verbosity)

    if interrupted:
        raise KeyboardInterrupt()

    return best_sol, objf(best_sol, D), objf(best_sol, D_c)
Ejemplo n.º 7
0
def main(overridden_args=None):
    ## 1. parse arguments

    parser = ArgumentParser(
        description=
        "Solve some .vrp problems with the algorithms built into VeRyPy.")
    parser.add_argument('-l',
                        dest='list_algorithms',
                        help="List the available heuristics and quit",
                        action="store_true")
    parser.add_argument(
        '-v',
        dest='verbosity',
        help=
        "Set the verbosity level (to completely disable debug output, run this script with 'python -O')",
        type=int,
        default=-1)
    parser.add_argument(
        '-a',
        dest='active_algorithms',
        help=
        "Algorithm to apply (argument can be set multiple times to enable multiple algorithms, or one can use 'all' or 'classical')",
        action='append')
    parser.add_argument(
        '-b',
        dest='objective',
        choices=['c', 'cost', 'K', 'vehicles'],
        help="Primary optimization oBjective (default is cost)",
        default="cost")
    parser.add_argument(
        '-m',
        dest='minimal_output',
        help=
        "Overrides the output options and prints only one line CSV report per solved instance",
        action="store_true")
    parser.add_argument(
        '-t',
        dest='print_elapsed_time',
        help="Print elapsed wall time for each solution attempt",
        action="store_true")
    parser.add_argument(
        '-c',
        dest='show_solution_cost',
        help="Display solution cost instead of solution length",
        action="store_true")
    parser.add_argument('-D',
                        dest='dist_weight_format',
                        choices=['ROUND', 'EXACT', 'TRUNCATE'],
                        help="Force distance matrix rounding")
    parser.add_argument(
        '-1',
        dest='use_single_iteration',
        help="Force the algorithms to use only single iteration.",
        action="store_true")
    parser.add_argument(
        '--iinfo',
        dest='print_instance_info',
        help="Print the instance info in the collected results",
        action="store_true")
    parser.add_argument(
        '--routes',
        dest='print_route_stat',
        help="Print per route statistics of the final solution",
        action="store_true")
    parser.add_argument('--vrph',
                        dest='print_vrph_sol',
                        help="Print the final solution in the VRPH format",
                        action="store_true")
    parser.add_argument(
        '--forbid',
        dest='forbid_algorithms',
        help=
        "Forbid applying algorithms (argument can set multiple times to forbid multiple algorithms)",
        action='append')
    parser.add_argument(
        '--simulate',
        dest='simulate',
        help=
        "Do not really invoke algorithms, can be used e.g. to test scripts",
        action="store_true")
    #TODO: consider adding more LS opts e.g. 2optstart, 3optstart
    parser.add_argument(
        '--post-optimize',
        dest='local_search_operators',
        choices=['2opt', '3opt'],
        help=
        "Do post-optimization with local search operator(s) (can set multiple)",
        action='append')
    parser.add_argument(
        "problem_file",
        help=
        "a path of a .vrp problem file, a directory containing .vrp files, or a text file of paths to .vrp files",
        action='append')

    if overridden_args:
        app_args = parser.parse_args(overridden_args)
    elif "-l" in sys.argv:
        print("Select at least one algorithm (with -a) from the list:",
              file=sys.stderr)
        print(_build_algorithm_help())
        sys.exit(1)
    elif len(sys.argv) == 1:
        print("Give at least one .vrp file and use -h to get help.",
              file=sys.stderr)
        sys.exit(1)
    else:
        app_args = parser.parse_args()

    # some further argument validation
    if not app_args.active_algorithms or app_args.list_algorithms:
        print("Select at least one algorithm (with -a) from the list:",
              file=sys.stderr)
        print(_build_algorithm_help())
        exit()
    if len(app_args.problem_file) == 0:
        print("Provide at least one .vrp file to solve", file=sys.stderr)
        exit()

    # get .vrp file list
    files_to_solve = shared_cli.get_a_problem_file_list(app_args.problem_file)

    # get algorithms
    algos = get_algorithms(app_args.active_algorithms)
    if app_args.forbid_algorithms:
        forbidden_algos = [
            algo_name_aliases[algo_name]
            for algo_name in app_args.forbid_algorithms
            if (algo_name in app_args.forbid_algorithms)
        ]
        algos = [a for a in algos if (a[0] not in forbidden_algos)]

    # get primary objective
    minimize_K = False
    if app_args.objective == 'K' or app_args.objective == 'vehicles':
        minimize_K = True

    run_single_iteration = False
    if app_args.use_single_iteration:
        run_single_iteration = True

    # get post-optimization local search move operators
    ls_ops = []
    ls_algo_names = []
    if app_args.local_search_operators:
        ls_algo_names = app_args.local_search_operators
        for ls_op_name in ls_algo_names:
            if ls_op_name == "2opt":
                ls_ops.append(do_2opt_move)
            if ls_op_name == "3opt":
                ls_ops.append(do_3opt_move)

    # verbosity
    if app_args.verbosity >= 0:
        shared_cli.set_logger_level(app_args.verbosity)

    # minimal header
    if app_args.minimal_output:
        print("algo;problem;is_feasible;f;K;t")

    ## 2. solve
    results = defaultdict(lambda: defaultdict(float))
    instance_data = dict()

    interrupted = False
    for pfn in files_to_solve:
        bn = path.basename(pfn).replace(".vrp",
                                        "").replace(".tsp",
                                                    "").replace(".pickle", "")

        try:
            N, points, dd_points, d, D, C, ewt, K, L, st = pickle.load(
                open(pfn, "rb"))
        except:
            N, points, dd_points, d, D, C, ewt = cvrp_io.read_TSPLIB_CVRP(pfn)
            K, L, st = cvrp_io.read_TSBLIB_additional_constraints(pfn)

        # We do not have point coodrinates, but we have D!
        if points is None:
            if dd_points is not None:
                points = dd_points
            else:
                points, ewt = cvrp_ops.generate_missing_coordinates(D)

        if app_args.dist_weight_format == "TRUNCATE":
            D = np.floor(D)
            ewt = "FLOOR_2D"
        if app_args.dist_weight_format == "ROUND":
            D = np.int(D)
            ewt = "EUC_2D"

        # Bake service time to D (if needed)
        D_c = cvrp_ops.D2D_c(D, st) if st else D

        for algo_abbreviation, algo_name, _, algo_f in algos:
            if not app_args.minimal_output:
                print("Solving %s with %s" % (bn, algo_name))
            start_t = time()
            sol = None
            try:
                if not app_args.simulate:
                    sol = algo_f(points, D_c, d, C, L, st, ewt,
                                 run_single_iteration, minimize_K)
            except (KeyboardInterrupt, Exception) as e:
                if type(e) is KeyboardInterrupt:
                    interrupted = True
                    # if interrupted on initial sol gen, return the best of those
                    if len(e.args) > 0 and type(e.args[0]) is list:
                        sol = e.args[0]
                    if not app_args.minimal_output:
                        print("WARNING: Interrupted solving %s with %s" %
                              (bn, algo_abbreviation),
                              file=sys.stderr)
                else:
                    if not app_args.minimal_output:
                        print("ERROR: Failed to solve %s with %s because %s" %
                              (bn, algo_abbreviation, str(e)),
                              file=sys.stderr)
                    sol = None

            if sol:
                sol = cvrp_ops.normalize_solution(sol)
                if app_args.show_solution_cost:
                    sol_q = cvrp_ops.calculate_objective(sol, D_c)
                else:
                    sol_q = cvrp_ops.calculate_objective(sol, D)
                sol_K = sol.count(0) - 1

                if app_args.local_search_operators:
                    if not app_args.minimal_output:
                        print("Postoptimize with %s ..." %
                              ", ".join(app_args.local_search_operators),
                              end="")
                    sol = do_local_search(ls_ops, sol, D, d, C, L)
                    sol = cvrp_ops.normalize_solution(sol)

                    if app_args.show_solution_cost:
                        ls_sol_q = cvrp_ops.calculate_objective(sol, D_c)
                    else:
                        ls_sol_q = cvrp_ops.calculate_objective(sol, D)
                    if ls_sol_q < sol_q:
                        if not app_args.minimal_output:
                            print(" improved by %.2f%%." %
                                  (1 - ls_sol_q / sol_q))
                        sol_q = ls_sol_q
                        sol_K = sol.count(0) - 1
                    else:
                        if not app_args.minimal_output:
                            print(" did not find improving moves.")
            else:
                sol_q = float('inf')

            elapsed_t = time() - start_t
            if app_args.minimal_output:
                print("%s;%s" % (algo_abbreviation, bn), end="")
                timecap_symbol = "*" if interrupted else ""
                if sol:
                    feasible = all(
                        cvrp_ops.check_solution_feasibility(
                            sol, D_c, d, C, L, st))
                    print(";%s;%.2f;%d;%.2f%s" % (str(feasible), sol_q, sol_K,
                                                  elapsed_t, timecap_symbol))
                else:
                    print(";False;inf;inf;%.2f%s" %
                          (elapsed_t, timecap_symbol))

            elif sol:
                # Minimal output is not enabled, print like crazy :)

                if app_args.print_elapsed_time:
                    print("Algorithm produced a solution in %.2f s\n" %
                          (elapsed_t))
                else:
                    #just a newline
                    print()

                tightness = None
                if C and sol_K:
                    tightness = (sum(d) / (C * sol_K))
                if not bn in instance_data or sol_K < instance_data[bn][1]:
                    #"N K C tightness L st"
                    instance_data[bn] = (N, sol_K, C, "%.3f" % tightness, L,
                                         st)

                shared_cli.print_problem_information(
                    points,
                    D_c,
                    d,
                    C,
                    L,
                    st,
                    tightness,
                    verbosity=app_args.verbosity)

                solution_print_verbosity = 3 if app_args.print_route_stat else 1
                shared_cli.print_solution_statistics(sol, D, D_c, d, C, L, st,
                                                     solution_print_verbosity)

                if app_args.print_vrph_sol:
                    print("SOLUTION IN VRPH FORMAT:")
                    print(" ".join(
                        str(n) for n in cvrp_io.as_VRPH_solution(sol)))
                print("\n")

            short_algo_name = algo_name
            results[bn][short_algo_name] = sol_q

            if interrupted:
                break  # algo loop
        if interrupted:
            break  # problem file loop

    ## Print collected results
    sys.stdout.flush()
    sys.stderr.flush()
    if not app_args.minimal_output and (len(results) > 1 or len(algos) > 1):
        print("\n")
        print_title = True
        ls_label = "+".join(ls_algo_names)
        for problem, algo_results in sorted(results.items()):
            algo_names = [ "%s+%s"%(algo_name,ls_label) if ls_algo_names else (algo_name)\
                           for algo_name in sorted(algo_results.keys())]

            if print_title:
                instance_fields = "instance\t"
                if PRINT_INSTANCE_DATA:
                    #"N K C tightness L st"
                    instance_fields += "N\tK*\tC\ttightness\tL\tst\t"
                print(instance_fields + "\t".join(algo_names))
                print_title = False
            print(problem, end="")
            if PRINT_INSTANCE_DATA:
                print("\t", end="")
                print("\t".join(str(e) for e in instance_data[problem]),
                      end="")
            for _, result in sorted(algo_results.items()):
                print("\t", result, end="")
            print()
    sys.stdout.flush()
    sys.stderr.flush()
Ejemplo n.º 8
0
#!/usr/bin/env python
# -*- coding: utf-8 -*-
###############################################################################
""" This file is a part of the VeRyPy classical vehicle routing problem
heuristic library and demonstrates the simple use case of solving a single
TSPLIB formatted problem instance file with a single heuristic algorithm and
printing the resulting solution route by route."""
###############################################################################

import cvrp_io
from classic_heuristics.parallel_savings import parallel_savings_init
from util import sol2routes

E_n51_k5_path = r"E-n51-k5.vrp"

problem = cvrp_io.read_TSPLIB_CVRP(E_n51_k5_path)

solution = parallel_savings_init(D=problem.distance_matrix,
                                 d=problem.customer_demands,
                                 C=problem.capacity_constraint)

for route_idx, route in enumerate(sol2routes(solution)):
    print("Route #%d : %s" % (route_idx + 1, route))