| 1 | /* $Id: ClpSimplexNonlinear.hpp 1665 2011-01-04 17:55:54Z lou $ */ |
| 2 | // Copyright (C) 2004, International Business Machines |
| 3 | // Corporation and others. All Rights Reserved. |
| 4 | // This code is licensed under the terms of the Eclipse Public License (EPL). |
| 5 | /* |
| 6 | Authors |
| 7 | |
| 8 | John Forrest |
| 9 | |
| 10 | */ |
| 11 | #ifndef ClpSimplexNonlinear_H |
| 12 | #define ClpSimplexNonlinear_H |
| 13 | |
| 14 | class ClpNonlinearInfo; |
| 15 | class ClpQuadraticObjective; |
| 16 | class ClpConstraint; |
| 17 | |
| 18 | #include "ClpSimplexPrimal.hpp" |
| 19 | |
| 20 | /** This solves non-linear LPs using the primal simplex method |
| 21 | |
| 22 | It inherits from ClpSimplexPrimal. It has no data of its own and |
| 23 | is never created - only cast from a ClpSimplexPrimal object at algorithm time. |
| 24 | If needed create new class and pass around |
| 25 | |
| 26 | */ |
| 27 | |
| 28 | class ClpSimplexNonlinear : public ClpSimplexPrimal { |
| 29 | |
| 30 | public: |
| 31 | |
| 32 | /**@name Description of algorithm */ |
| 33 | //@{ |
| 34 | /** Primal algorithms for reduced gradient |
| 35 | At present we have two algorithms: |
| 36 | |
| 37 | */ |
| 38 | /// A reduced gradient method. |
| 39 | int primal(); |
| 40 | /** Primal algorithm for quadratic |
| 41 | Using a semi-trust region approach as for pooling problem |
| 42 | This is in because I have it lying around |
| 43 | |
| 44 | */ |
| 45 | int primalSLP(int numberPasses, double deltaTolerance); |
| 46 | /** Primal algorithm for nonlinear constraints |
| 47 | Using a semi-trust region approach as for pooling problem |
| 48 | This is in because I have it lying around |
| 49 | |
| 50 | */ |
| 51 | int primalSLP(int numberConstraints, ClpConstraint ** constraints, |
| 52 | int numberPasses, double deltaTolerance); |
| 53 | |
| 54 | /** Creates direction vector. note longArray is long enough |
| 55 | for rows and columns. If numberNonBasic 0 then is updated |
| 56 | otherwise mode is ignored and those are used. |
| 57 | Norms are only for those > 1.0e3*dualTolerance |
| 58 | If mode is nonzero then just largest dj */ |
| 59 | void directionVector (CoinIndexedVector * longArray, |
| 60 | CoinIndexedVector * spare1, CoinIndexedVector * spare2, |
| 61 | int mode, |
| 62 | double & normFlagged, double & normUnflagged, |
| 63 | int & numberNonBasic); |
| 64 | /// Main part. |
| 65 | int whileIterating (int & pivotMode); |
| 66 | /** |
| 67 | longArray has direction |
| 68 | pivotMode - |
| 69 | 0 - use all dual infeasible variables |
| 70 | 1 - largest dj |
| 71 | while >= 10 trying startup phase |
| 72 | Returns 0 - can do normal iteration (basis change) |
| 73 | 1 - no basis change |
| 74 | 2 - if wants singleton |
| 75 | 3 - if time to re-factorize |
| 76 | If sequenceIn_ >=0 then that will be incoming variable |
| 77 | */ |
| 78 | int pivotColumn(CoinIndexedVector * longArray, |
| 79 | CoinIndexedVector * rowArray, |
| 80 | CoinIndexedVector * columnArray, |
| 81 | CoinIndexedVector * spare, |
| 82 | int & pivotMode, |
| 83 | double & solutionError, |
| 84 | double * array1); |
| 85 | /** Refactorizes if necessary |
| 86 | Checks if finished. Updates status. |
| 87 | lastCleaned refers to iteration at which some objective/feasibility |
| 88 | cleaning too place. |
| 89 | |
| 90 | type - 0 initial so set up save arrays etc |
| 91 | - 1 normal -if good update save |
| 92 | - 2 restoring from saved |
| 93 | */ |
| 94 | void statusOfProblemInPrimal(int & lastCleaned, int type, |
| 95 | ClpSimplexProgress * progress, |
| 96 | bool doFactorization, |
| 97 | double & bestObjectiveWhenFlagged); |
| 98 | /** Do last half of an iteration. |
| 99 | Return codes |
| 100 | Reasons to come out normal mode |
| 101 | -1 normal |
| 102 | -2 factorize now - good iteration |
| 103 | -3 slight inaccuracy - refactorize - iteration done |
| 104 | -4 inaccuracy - refactorize - no iteration |
| 105 | -5 something flagged - go round again |
| 106 | +2 looks unbounded |
| 107 | +3 max iterations (iteration done) |
| 108 | |
| 109 | */ |
| 110 | int pivotNonlinearResult(); |
| 111 | //@} |
| 112 | |
| 113 | }; |
| 114 | #endif |
| 115 | |