Line data Source code
1 : /****************************************************************************/
2 : // Eclipse SUMO, Simulation of Urban MObility; see https://eclipse.dev/sumo
3 : // Copyright (C) 2002-2024 German Aerospace Center (DLR) and others.
4 : // This program and the accompanying materials are made available under the
5 : // terms of the Eclipse Public License 2.0 which is available at
6 : // https://www.eclipse.org/legal/epl-2.0/
7 : // This Source Code may also be made available under the following Secondary
8 : // Licenses when the conditions for such availability set forth in the Eclipse
9 : // Public License 2.0 are satisfied: GNU General Public License, version 2
10 : // or later which is available at
11 : // https://www.gnu.org/licenses/old-licenses/gpl-2.0-standalone.html
12 : // SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-or-later
13 : /****************************************************************************/
14 : /// @file GawronCalculator.h
15 : /// @author Daniel Krajzewicz
16 : /// @author Michael Behrisch
17 : /// @author Jakob Erdmann
18 : /// @date Sept 2002
19 : ///
20 : // Calculators for route costs and probabilities
21 : /****************************************************************************/
22 : #pragma once
23 : #include <config.h>
24 :
25 : #include <vector>
26 : #include <map>
27 :
28 :
29 : // ===========================================================================
30 : // class definitions
31 : // ===========================================================================
32 : /**
33 : * @class GawronCalculator
34 : * @brief Cost calculation with Gawron's method.
35 : */
36 : template<class R, class E, class V>
37 : class GawronCalculator : public RouteCostCalculator<R, E, V> {
38 : public:
39 : /// Constructor
40 3569 : GawronCalculator(const double beta, const double a) : myBeta(beta), myA(a) {}
41 :
42 : /// Destructor
43 3569 : virtual ~GawronCalculator() {}
44 :
45 225839 : void setCosts(R* route, const double costs, const bool isActive = false) const {
46 225839 : if (isActive) {
47 85154 : route->setCosts(costs);
48 : } else {
49 140685 : route->setCosts(myBeta * costs + ((double) 1.0 - myBeta) * route->getCosts());
50 : }
51 225839 : }
52 :
53 : /** @brief calculate the probabilities */
54 85154 : void calculateProbabilities(std::vector<R*> alternatives, const V* const /* veh */, const SUMOTime /* time */) {
55 225839 : for (typename std::vector<R*>::iterator i = alternatives.begin(); i != alternatives.end() - 1; i++) {
56 140685 : R* pR = *i;
57 345286 : for (typename std::vector<R*>::iterator j = i + 1; j != alternatives.end(); j++) {
58 204601 : R* pS = *j;
59 : // see [Gawron, 1998] (4.2)
60 204601 : const double delta =
61 204601 : (pS->getCosts() - pR->getCosts()) /
62 204601 : (pS->getCosts() + pR->getCosts());
63 : // see [Gawron, 1998] (4.3a, 4.3b)
64 204601 : double newPR = gawronF(pR->getProbability(), pS->getProbability(), delta);
65 204601 : double newPS = pR->getProbability() + pS->getProbability() - newPR;
66 204601 : if (std::isnan(newPR) || std::isnan(newPS)) {
67 : newPR = pS->getCosts() > pR->getCosts()
68 0 : ? (double) 1. : 0;
69 : newPS = pS->getCosts() > pR->getCosts()
70 0 : ? 0 : (double) 1.;
71 : }
72 : newPR = MIN2((double) MAX2(newPR, (double) 0), (double) 1);
73 : newPS = MIN2((double) MAX2(newPS, (double) 0), (double) 1);
74 204601 : pR->setProbability(newPR);
75 204601 : pS->setProbability(newPS);
76 : }
77 : }
78 85154 : }
79 :
80 : private:
81 : /** @brief Performs the gawron - f() function
82 : From "Dynamic User Equilibria..." */
83 204601 : double gawronF(const double pdr, const double pds, const double x) const {
84 204601 : if (pdr * gawronG(myA, x) + pds == 0) {
85 : return std::numeric_limits<double>::max();
86 : }
87 409202 : return (pdr * (pdr + pds) * gawronG(myA, x)) /
88 204601 : (pdr * gawronG(myA, x) + pds);
89 : }
90 :
91 : /** @brief Performs the gawron - g() function
92 : From "Dynamic User Equilibria..." */
93 : double gawronG(const double a, const double x) const {
94 613803 : if (((1.0 - (x * x)) == 0)) {
95 : return std::numeric_limits<double>::max();
96 : }
97 613803 : return (double) exp((a * x) / (1.0 - (x * x)));
98 : }
99 :
100 : private:
101 : /// @brief gawron beta - value
102 : const double myBeta;
103 :
104 : /// @brief gawron a - value
105 : const double myA;
106 :
107 : private:
108 : /** @brief invalidated assignment operator */
109 : GawronCalculator& operator=(const GawronCalculator& s);
110 :
111 : };
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