/*

     This file is part of Combean.

     Combean is free software; you can redistribute it and/or modify

     it under the terms of the GNU General Public License as published by

     the Free Software Foundation; either version 2 of the License, or

     (at your option) any later version.

     Combean is distributed in the hope that it will be useful,

     but WITHOUT ANY WARRANTY; without even the implied warranty of

     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

     GNU General Public License for more details.

     You should have received a copy of the GNU General Public License

     along with Foobar; if not, write to the Free Software

     Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

 */

 package net.sourceforge.combean.test.mathprog.grooml;

 import net.sourceforge.combean.interfaces.mathprog.linalg.VectorOrientation;

 import net.sourceforge.combean.mathprog.lp.model.LPModelIndexImpl;

 import net.sourceforge.combean.mathprog.grooml.GExpression;

 import net.sourceforge.combean.mathprog.grooml.GroomlInterpreter;

 import net.sourceforge.combean.mathprog.grooml.GLPSolver;

 class TestGLPSolver extends GroovyTestCase {

     private GroomlInterpreter builder;

     private GLPSolver solver;

     void setUp() {

         this.solver = new GLPSolver();

         this.builder = new GroomlInterpreter();

     }

         void testSimpleEquation() {

             def coeff = [1:-2.0, 2:2.0];

             builder.load{

                 vars("x", 1..2) { [coeff[it], -1..1] };

                 row("foo") {

                     sum(i:1..2) { "x[$i]" } | 1.0

                 }

             }

             solveAndCheck(-2.0, ["x[1]":1.0, "x[2]":0.0], 0.001);

         }

         void testSimpleEquationWithListIndex() {

             def idxSet = ["a", "b"];

             builder.load{

                     def coeff = [a:-2.0, b:2.0];

                 vars("x", [it:idxSet]) { [coeff[it], -1..1] };

                 row("foo") {

                     sum(i:idxSet) { "x[$i]" } | 1.0

                 }

             }

             solveAndCheck(-2.0, ["x[a]":1.0, "x[b]":0.0], 0.001);

         }

         void testMultipleVariables() {

             builder.load{

                 var("x") { [-2, -1..1] };

                 var("y") { [2, -1..1] };

                 row("foo") {

                     expr("x[]") + "y[]" | 1.0

                 }

             }

             solveAndCheck(-2.0, ["x[]":1.0, "y[]":0.0], 0.001);

         }

         private void solveAndCheck(double expectedSolution, Map varIdToExpectedVal,

                 double precision) {

             this.solver.loadModel(this.builder.getModel());

             this.solver.solve();

             assertEquals(expectedSolution, solver.LPSolver.getSolutionValue(),

                     precision);

             varIdToExpectedVal.keySet().each {

                 assertEquals(varIdToExpectedVal[it], solver.getSolution(it),

                         precision);

             }

         }

 }