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transport11.cpp
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1/*
2 * GAMS - General Algebraic Modeling System C++ API
3 *
4 * Copyright (c) 2017-2023 GAMS Software GmbH <support@gams.com>
5 * Copyright (c) 2017-2023 GAMS Development Corp. <support@gams.com>
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a copy
8 * of this software and associated documentation files (the "Software"), to deal
9 * in the Software without restriction, including without limitation the rights
10 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11 * copies of the Software, and to permit persons to whom the Software is
12 * furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included in all
15 * copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
20 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
23 * SOFTWARE.
24 */
25#include "gams.h"
26
27#include <iostream>
28#include <map>
29#include <tuple>
30#include <vector>
31
32using namespace gams;
33using namespace std;
34
36string getBaseModelText()
37{
38 return "$onempty \n"
39 " Sets \n"
40 " i(*) canning plants / / \n"
41 " j(*) markets / / \n"
42 " \n"
43 " Parameters \n"
44 " a(i) capacity of plant i in cases / / \n"
45 " b(j) demand at market j in cases / / \n"
46 " d(i,j) distance in thousands of miles / / \n"
47 " Scalar f freight in dollars per case per thousand miles /0/; \n"
48 " \n"
49 " Parameter c(i,j) transport cost in thousands of dollars per case ; \n"
50 " \n"
51 " c(i,j) = f * d(i,j) / 1000 ; \n"
52 " \n"
53 " Variables \n"
54 " x(i,j) shipment quantities in cases \n"
55 " z total transportation costs in thousands of dollars ; \n"
56 " \n"
57 " Positive Variable x ; \n"
58 " \n"
59 " Equations \n"
60 " cost define objective function \n"
61 " supply(i) observe supply limit at plant i \n"
62 " demand(j) satisfy demand at market j ; \n"
63 " \n"
64 " cost .. z =e= sum((i,j), c(i,j)*x(i,j)) ; \n"
65 " \n"
66 " supply(i) .. sum(j, x(i,j)) =l= a(i) ; \n"
67 " \n"
68 " demand(j) .. sum(i, x(i,j)) =g= b(j) ; \n"
69 " \n"
70 " Model transport /all/ ; \n"
71 " \n"
72 " Solve transport using lp minimizing z ; \n";
73}
74
76string getModelText()
77{
78 return "$if not set gdxincname $abort 'no include file name for data file provided'\n"
79 "$gdxin %gdxincname% \n"
80 "$onMulti \n"
81 "$load i j a b d f \n"
82 "$gdxin \n"
83 " \n"
84 " Display x.l, x.m ; \n";
85}
86
88void createSaveRestart(int argc, char* argv[], const string &checkpointName)
89{
90 GAMSWorkspaceInfo wsInfo;
91 if (argc > 1)
92 wsInfo.setSystemDirectory(argv[1]);
93 wsInfo.setWorkingDirectory("." +(cPathSep+ checkpointName));
94 GAMSWorkspace ws(wsInfo);
95
96 GAMSJob j1 = ws.addJobFromString(getBaseModelText());
97 GAMSOptions opt = ws.addOptions();
98 opt.setAction(GAMSOptions::EAction::CompileOnly);
99
100 auto checkpoint = ws.workingDirectory() + cPathSep + checkpointName;
101 GAMSCheckpoint cp = ws.addCheckpoint(checkpoint);
102 j1.run(opt, cp);
103}
104
110int main(int argc, char* argv[])
111{
112 cout << "---------- Transport 11 --------------" << endl;
113
114 try {
115 // Create a save/restart file usually supplied by an application provider
116 // We create it for demonstration purpose
117 std::string cpName = "tbase";
118 createSaveRestart(argc, argv, cpName);
119
120 // define some data by using C++ data structures
121 vector<string> plants { "Seattle", "San-Diego" };
122 vector<string> markets {"New-York", "Chicago", "Topeka" };
123 map<string, double> capacity {
124 { "Seattle", 350.0 }, { "San-Diego", 600.0 }
125 };
126 map<string, double> demand {
127 { "New-York", 325.0 }, { "Chicago", 300.0 }, { "Topeka", 275.0 }
128 };
129 map<tuple<string,string>, double> distance {
130 { make_tuple("Seattle", "New-York"), 2.5 },
131 { make_tuple("Seattle", "Chicago"), 1.7 },
132 { make_tuple("Seattle", "Topeka"), 1.8 },
133 { make_tuple("San-Diego", "New-York"), 2.5 },
134 { make_tuple("San-Diego", "Chicago"), 1.8 },
135 { make_tuple("San-Diego", "Topeka"), 1.4 }
136 };
137
138 GAMSWorkspaceInfo wsInfo;
139 if (argc > 1)
140 wsInfo.setSystemDirectory(argv[1]);
141 wsInfo.setWorkingDirectory("." +(cPathSep+ cpName));
142 GAMSWorkspace ws(wsInfo);
143 ws.gamsLib("trnsport");
144
145 // prepare a GAMSDatabase with data from the C++ data structures
146 GAMSDatabase db = ws.addDatabase();
147
148 GAMSSet i = db.addSet("i", 1, "canning plants");
149 for (auto plant : plants)
150 i.addRecord(plant);
151
152 GAMSSet j = db.addSet("j", 1, "markets");
153 for (auto market : markets)
154 j.addRecord(market);
155
156 GAMSParameter a = db.addParameter("a", "capacity of plant i in cases", i);
157 for (auto plant : plants)
158 a.addRecord(plant).setValue(capacity[plant]);
159
160 GAMSParameter b = db.addParameter("b", "demand at market j in cases", j);
161 for (auto market : markets)
162 b.addRecord(market).setValue(demand[market]);
163
164 GAMSParameter d = db.addParameter("d", "distance in thousands of miles", i, j);
165 for (auto t : distance) {
166 auto tuple = t.first;
167 auto t1 = get<0>(tuple);
168 auto t2 = get<1>(tuple);
169 d.addRecord(t1, t2).setValue(distance[tuple]);
170 }
171
172 GAMSParameter f = db.addParameter("f", "freight in dollars per case per thousand miles");
173 f.addRecord().setValue(90);
174
175 // run a job using data from the created GAMSDatabase
176 GAMSCheckpoint cpBase = ws.addCheckpoint("tbase");
177 GAMSOptions opt = ws.addOptions();
178 GAMSJob t4 = ws.addJobFromString(getModelText(), cpBase);
179 opt.setDefine("gdxincname", db.name());
180 opt.setAllModelTypes("xpress");
181 t4.run(opt, db);
182 for (auto record : t4.outDB().getVariable("x"))
183 cout << "x(" << record.key(0) << "," << record.key(1) << "): level=" << record.level() <<
184 " marginal=" << record.marginal() << endl;
185
186 } catch (GAMSException &ex) {
187 cout << "GAMSException occured: " << ex.what() << endl;
188 } catch (exception &ex) {
189 cout << ex.what() << endl;
190 }
191 return 0;
192}
gams::GAMSDatabase::addSet
GAMSSet addSet(const std::string &name, const int dimension, const std::string &explanatoryText="", GAMSEnum::SetType setType=GAMSEnum::SetType::Multi)
gams::GAMSDatabase::addParameter
GAMSParameter addParameter(const std::string &name, const int dimension, const std::string &explanatoryText="")
gams::GAMSDatabase::name
std::string name()
gams::GAMSDatabase::getVariable
GAMSVariable getVariable(const std::string &name)
gams::GAMSJob::outDB
GAMSDatabase outDB()
gams::GAMSOptions::setAllModelTypes
void setAllModelTypes(const std::string &solver)
gams::GAMSOptions::setDefine
void setDefine(const std::string &key, const std::string &value)
gams::GAMSOptions::setAction
void setAction(const GAMSOptions::EAction::EActionEnum value)
gams::GAMSParameterRecord::setValue
void setValue(const double val)
gams::GAMSParameter::addRecord
GAMSParameterRecord addRecord(const std::vector< std::string > &keys)
gams::GAMSSet::addRecord
GAMSSetRecord addRecord(const std::vector< std::string > &keys)
gams::GAMSWorkspaceInfo::setSystemDirectory
void setSystemDirectory(std::string systemDir)
gams::GAMSWorkspaceInfo::setWorkingDirectory
void setWorkingDirectory(std::string workingDir)
gams::GAMSWorkspace::workingDirectory
std::string workingDirectory() const
gams::GAMSWorkspace::addOptions
GAMSOptions addOptions()
gams::GAMSWorkspace::addJobFromString
GAMSJob addJobFromString(const std::string &gamsSource, const std::string &jobName="")
gams::GAMSWorkspace::addCheckpoint
GAMSCheckpoint addCheckpoint(const std::string &checkpointName="")
getBaseModelText
string getBaseModelText()
Get model as string.
Definition: transport11.cpp:36
createSaveRestart
void createSaveRestart(int argc, char *argv[], const string &checkpointName)
Create Save and Restart checkpoint.
Definition: transport11.cpp:88
getModelText
string getModelText()
Get model as string.
Definition: transport11.cpp:76