001/******************************************************************************* 002 * Copyright (c) 2016 Pablo Pavon Mariņo. 003 * All rights reserved. This program and the accompanying materials 004 * are made available under the terms of the GNU Lesser Public License v2.1 005 * which accompanies this distribution, and is available at 006 * http://www.gnu.org/licenses/lgpl.html 007 ******************************************************************************/ 008 009 010 011 012 013 014 015 016 017 018package com.net2plan.examples.ocnbook.offline; 019 020import java.io.File; 021import java.util.ArrayList; 022import java.util.List; 023import java.util.Map; 024 025import cern.colt.matrix.tdouble.DoubleFactory1D; 026import cern.colt.matrix.tdouble.DoubleFactory2D; 027import cern.colt.matrix.tdouble.DoubleMatrix1D; 028import cern.colt.matrix.tdouble.DoubleMatrix2D; 029import cern.colt.matrix.tdouble.DoubleMatrix3D; 030import cern.jet.math.tdouble.DoubleFunctions; 031 032import com.jom.DoubleMatrixND; 033import com.jom.OptimizationProblem; 034import com.net2plan.interfaces.networkDesign.Configuration; 035import com.net2plan.interfaces.networkDesign.Demand; 036import com.net2plan.interfaces.networkDesign.IAlgorithm; 037import com.net2plan.interfaces.networkDesign.Link; 038import com.net2plan.interfaces.networkDesign.Net2PlanException; 039import com.net2plan.interfaces.networkDesign.NetPlan; 040import com.net2plan.utils.Constants.RoutingType; 041import com.net2plan.utils.InputParameter; 042import com.net2plan.utils.StringUtils; 043import com.net2plan.utils.Triple; 044 045/** 046 * Finds the multiperiod (e.g. subsequent years) routing and capacity acquisitions with a MILP formulation 047 * @net2plan.description 048 * @net2plan.keywords Capacity assignment (CA), Modular capacities, Flow assignment (FA), Multiperiod optimization, JOM 049 * @net2plan.ocnbooksections Section 5.2.3 050 * @net2plan.inputParameters 051 * @author Pablo Pavon-Marino 052 */ 053public class Offline_cfa_xpMultiperiodModularCapacities implements IAlgorithm 054{ 055 private InputParameter rootOfNameOfInputTrafficFiles = new InputParameter ("rootOfNameOfInputTrafficFiles", "multiPeriodModularCapacities", "Root of the names of the traffic files. If the root is \"XXX\", the files are XXX_tm0.n2p, XXX_tm1.n2p, ..."); 056 private InputParameter rootOfNameOfOutputFiles = new InputParameter ("rootOfNameOfOutputFiles", "multiPeriodModularCapacities", "Root of the names of the output files. One per input traffic file. If the root is \"XXX\", the files are XXX_res_tm0.n2p, XXX_res_tm1.n2p, ..."); 057 private InputParameter k = new InputParameter ("k", (int) 5 , "Maximum number of admissible paths per demand" , 1 , Integer.MAX_VALUE); 058 private InputParameter shortestPathType = new InputParameter ("shortestPathType", "#select# hops km" , "Criteria to compute the shortest path. Valid values: 'hops' or 'km'"); 059 private InputParameter nonBifurcatedRouting = new InputParameter ("nonBifurcatedRouting", false , "True if the routing is constrained to be non-bifurcated"); 060 private InputParameter maxLengthInKm = new InputParameter ("maxLengthInKm", (double) 2000 , "Paths longer than this are considered not admissible. A non-positive number means this limit does not exist"); 061 private InputParameter solverName = new InputParameter ("solverName", "#select# glpk cplex", "The solver name to be used by JOM. GLPK is free, CPLEX commercial. Both GLPK and CPLEX solve linear problems w/w.o integer contraints."); 062 private InputParameter solverLibraryName = new InputParameter ("solverLibraryName", "" , "The solver library full or relative path, to be used by JOM. Leave blank to use JOM default."); 063 private InputParameter maxSolverTimeInSeconds = new InputParameter ("maxSolverTimeInSeconds", (double) -1 , "Maximum time granted to the solver to solve the problem. If this time expires, the solver returns the best solution found so far (if a feasible solution is found)"); 064 private InputParameter costPerCapacityModuleType = new InputParameter ("costPerCapacityModuleType", "1 3 6", "The cost of each module of the given type"); 065 private InputParameter capacityOfEachCapacityModuleType = new InputParameter ("capacityOfEachCapacityModuleType", "10 40 100", "The capacity of each module of the given type"); 066 private InputParameter costReductionFactor = new InputParameter ("costReductionFactor", (double) 1 , "The cost of each element at period t is the cost at the previous period multiplied by this. Typically below one since things tend to decrease its price because of improvement in manufacturing" , 0 , true , Double.MAX_VALUE , true); 067 068 @Override 069 public String executeAlgorithm(NetPlan netPlan, Map<String, String> algorithmParameters, Map<String, String> net2planParameters) 070 { 071 /* Initialize all InputParameter objects defined in this object (this uses Java reflection) */ 072 InputParameter.initializeAllInputParameterFieldsOfObject(this, algorithmParameters); 073 if (!shortestPathType.getString().equalsIgnoreCase("km") && !shortestPathType.getString().equalsIgnoreCase("hops")) 074 throw new Net2PlanException("Wrong shortestPathType parameter"); 075 final DoubleMatrix1D u_k = DoubleFactory1D.dense.make (StringUtils.toDoubleArray(StringUtils.split(capacityOfEachCapacityModuleType.getString()))); 076 final DoubleMatrix1D c_k0 = DoubleFactory1D.dense.make (StringUtils.toDoubleArray(StringUtils.split(costPerCapacityModuleType.getString()))); 077 final int K = (int) u_k.size (); // number of types of capacity modules 078 if (K == 0) throw new Net2PlanException ("No capacity modules defined"); 079 if (c_k0.size() != K) throw new Net2PlanException ("The number of costs should be equal to the number of types of capacity modules"); 080 if (u_k.getMinLocation() [0] < 0) throw new Net2PlanException ("Capacities of the modules cannot be negative"); 081 if (c_k0.getMinLocation() [0] < 0) throw new Net2PlanException ("Costs of the modules cannot be negative"); 082 083 /* Initialize variables */ 084 final int N = netPlan.getNumberOfNodes (); 085 final int E = netPlan.getNumberOfLinks (); 086 final double PRECISION_FACTOR = Double.parseDouble(net2planParameters.get("precisionFactor")); 087 if (E == 0) throw new Net2PlanException("This algorithm requires a topology with links"); 088 089 /* Remove all unicast routed traffic. Any multicast routed traffic is kept */ 090 netPlan.removeAllUnicastRoutingInformation(); 091 netPlan.setRoutingType(RoutingType.SOURCE_ROUTING); 092 netPlan.setTrafficMatrix(DoubleFactory2D.dense.make (N,N,1.0)); // just to create the demands 093 094 /* Add all the k-shortest candidate routes to the netPlan object carrying no traffic */ 095 final DoubleMatrix1D linkCostVectorForCandidatePathList = shortestPathType.getString().equalsIgnoreCase("hops")? DoubleFactory1D.dense.make (E , 1.0) : netPlan.getVectorLinkLengthInKm(); 096 097 netPlan.addRoutesFromCandidatePathList(linkCostVectorForCandidatePathList.toArray() , "K", Integer.toString(k.getInt ()), "maxLengthInKm", Double.toString(maxLengthInKm.getDouble () > 0? maxLengthInKm.getDouble () : Double.MAX_VALUE)); 098 final int P = netPlan.getNumberOfRoutes(); 099 100 /* Create the netPlan files, one per interval */ 101 ArrayList<NetPlan> netPlanFiles = new ArrayList<NetPlan> (); 102 while (true) 103 { 104 try 105 { 106 DoubleMatrix2D thisIntervalTrafficMatrix = new NetPlan(new File (rootOfNameOfInputTrafficFiles.getString() + "_tm" + netPlanFiles.size () + ".n2p")).getMatrixNode2NodeOfferedTraffic(); 107 if (thisIntervalTrafficMatrix.rows () != N) throw new Net2PlanException ("The number of nodes in traffic matrix: " + rootOfNameOfInputTrafficFiles.getString() + "_tm" + netPlanFiles.size () + ".n2p (" + thisIntervalTrafficMatrix.rows() + ") is not correct (" + N + ")"); 108 NetPlan netPlanToAdd = netPlan.copy (); 109 for (Demand d : netPlanToAdd.getDemands()) d.setOfferedTraffic(thisIntervalTrafficMatrix.get (d.getIngressNode().getIndex() , d.getEgressNode().getIndex())); 110 netPlanFiles.add (netPlanToAdd); 111 } catch (Exception e) { e.printStackTrace(); break; } 112 } 113 final int T = netPlanFiles.size(); 114 115 /* Compute the costs */ 116 final DoubleMatrix2D c_kt = DoubleFactory2D.dense.make (K,T); 117 c_kt.viewColumn(0).assign (c_k0); 118 for (int t = 1 ; t < T ; t ++) 119 c_kt.viewColumn(t).assign (c_kt.viewColumn (t-1).copy ()).assign(DoubleFunctions.mult(costReductionFactor.getDouble())); 120 121 /* Create the optimization problem object (JOM library) */ 122 OptimizationProblem op = new OptimizationProblem(); 123 124 /* Set some input parameters to the problem */ 125 op.setInputParameter("A_dp", netPlan.getMatrixDemand2RouteAssignment()); /* 1 in position (d,p) if demand d is served by path p, 0 otherwise */ 126 op.setInputParameter("A_ep", netPlan.getMatrixLink2RouteAssignment()); /* 1 in position (e,p) if link e is traversed by path p, 0 otherwise */ 127 DoubleMatrix2D h_dt = DoubleFactory2D.dense.make (N*(N-1),T); 128 DoubleMatrix2D h_pt = DoubleFactory2D.dense.make (P,T); 129 for (int t = 0; t < T ; t ++) 130 { 131 h_dt.viewColumn(t).assign (netPlanFiles.get(t).getVectorDemandOfferedTraffic()); 132 h_pt.viewColumn(t).assign (netPlanFiles.get(t).getVectorRouteOfferedTrafficOfAssociatedDemand()); 133 } 134 op.setInputParameter("h_dt", h_dt); /* for each demand and time interval , its offered traffic */ 135 op.setInputParameter("h_pt", h_pt); /* for each path and time interval , the offered traffic of its demand */ 136 op.setInputParameter("u_k", u_k , "row"); /* The capacity of each module of type k */ 137 op.setInputParameter("c_kt", c_kt); /* The cost of a module of type k, acquired to be used starting in interval t */ 138 op.setInputParameter("onesT", DoubleFactory1D.dense.make (T,1.0) , "row"); /* a vector of ones of size T */ 139 DoubleMatrix2D timeAccumulationMatrix = DoubleFactory2D.dense.make (T,T); for (int t1 = 0 ; t1 < T; t1 ++) for (int t2 = t1 ; t2 < T ; t2++) timeAccumulationMatrix.set(t1,t2,1.0); 140 op.setInputParameter("T_tt", timeAccumulationMatrix); /* 1 if column >= row: if the time of acquisition (row) is equal or higher than the time if observation (t2) */ 141 142 op.addDecisionVariable("xx_pt", nonBifurcatedRouting.getBoolean() , new int[] { P , T }, 0, 1); /* the FRACTION of traffic of demand d(p) that is carried by p in each time interval */ 143 op.addDecisionVariable("a_ket", true , new int[] { K , E , T }, 0, 1); /* the number of elements of type k, acquired at time t, and placed at link e (in t and all intervals after t) */ 144 145 op.setObjectiveFunction("minimize", "sum (c_kt .* sum(a_ket,2)) "); /* sum of the cost of all the elements acquired, at the moment of acquisition */ 146 op.addConstraint("A_dp * xx_pt == 1"); /* for each demand, the 100% of the traffic is carried (summing the associated paths) in any time period */ 147 op.addConstraint("A_ep * (xx_pt .* h_pt) <= sum(u_k * a_ket,1) * T_tt"); /* the traffic in each link cannot exceed its capacity in any time period */ 148 149 op.solve(solverName.getString (), "solverLibraryName", solverLibraryName.getString () , "maxSolverTimeInSeconds" , maxSolverTimeInSeconds.getDouble ()); 150 151 /* If no solution is found, quit */ 152 if (op.feasibleSolutionDoesNotExist()) throw new Net2PlanException("The problem has no feasible solution"); 153 if (!op.solutionIsFeasible()) throw new Net2PlanException("A feasible solution was not found"); 154 155 /* Save the solution found in the netPlan object */ 156 final DoubleMatrix2D xx_pt = op.getPrimalSolution("xx_pt").view2D (); 157 final DoubleMatrix3D a_ket = op.getPrimalSolution("a_ket").view3D("sparse"); 158 159 for (int t = 0 ; t < T ; t ++) 160 { 161 NetPlan thisNp = netPlanFiles.get(t); 162 final DoubleMatrix1D h_p = thisNp.getVectorRouteOfferedTrafficOfAssociatedDemand(); 163 final DoubleMatrix1D x_p = xx_pt.viewColumn(t).copy().assign (h_p , DoubleFunctions.mult); 164 System.out.println ("h_p: " + h_p); 165 thisNp.setVectorRouteCarriedTrafficAndOccupiedLinkCapacities(x_p , x_p); 166 for (Link link : thisNp.getLinks ()) 167 { 168 final int e = link.getIndex (); 169 double linkCapacityAccumulatingPreviosModules = 0; for (int t1 = 0; t1 <= t ; t1 ++) for (int k = 0 ; k < K ; k ++) linkCapacityAccumulatingPreviosModules += u_k.get(k) * a_ket.get(k,e,t1); 170 link.setCapacity(linkCapacityAccumulatingPreviosModules); 171 for (int k = 0 ; k < K ; k ++) link.setAttribute ("numNewModulesType_" + k , "" + a_ket.get (k,e,t)); 172 } 173 thisNp.removeAllRoutesUnused(PRECISION_FACTOR); // routes with zero traffic (or close to zero, with PRECISION_FACTOR tolerance) 174 thisNp.saveToFile(new File (rootOfNameOfOutputFiles.getString() + "_res_tm" + netPlanFiles.size () + ".n2p")); 175 if (t == 0) netPlan.assignFrom (thisNp); 176 if (thisNp.getVectorLinkOversubscribedTraffic().zSum () > PRECISION_FACTOR) throw new RuntimeException ("Bad: " + thisNp.getVectorLinkOversubscribedTraffic().zSum ()); 177 if (thisNp.getDemandTotalBlockedTraffic() > PRECISION_FACTOR) throw new RuntimeException ("Bad: " + thisNp.getDemandTotalBlockedTraffic()); 178 } 179 180 return "Ok!: The solution found is guaranteed to be optimal: " + op.solutionIsOptimal() + ". Total cost = " + op.parseExpression("sum (c_kt .* sum(a_ket,2))").evaluate("a_ket" , new DoubleMatrixND (a_ket)); 181 } 182 183 @Override 184 public String getDescription() 185 { 186 return "Given a network with a set of given nodes, and links, and a given a sequence of offered traffic matrices in the network, corresponding to the (typically increasing) traffic of successive periods (e.g. each for one year). The link capacities are constrained to be modular: selectable among a set of user-defined capacity modules. Each capacity module type is characterized by its capacity and its cost. We assume that the costs of the capacity modules decrease along time, according to a cost reduction factor. Then, the algorithm should find for each of the successive periods: (i) the routing of the traffic in each period, (ii) how many NEW modules of capacity are installed in each link. Once a capacity module is installed in a link, we assume that it is never moved. The optimization target is minimizing the total cost along all the periods. This algorithm optimizes the problem solving a flow-path formulation using JOM."; 187 } 188 189 190 @Override 191 public List<Triple<String, String, String>> getParameters() 192 { 193 /* Returns the parameter information for all the InputParameter objects defined in this object (uses Java reflection) */ 194 return InputParameter.getInformationAllInputParameterFieldsOfObject(this); 195 } 196}