net.sf.cpsolver.coursett.criteria

## Class Perturbations

- java.lang.Object
- - net.sf.cpsolver.ifs.criteria.AbstractCriterion<Lecture,Placement>
  - - net.sf.cpsolver.coursett.criteria.TimetablingCriterion
    - - net.sf.cpsolver.coursett.criteria.Perturbations

- All Implemented Interfaces:
    Criterion<Lecture,Placement>, InfoProvider<Lecture>, ModelListener<Lecture,Placement>

      public class Perturbations
      extends TimetablingCriterion

  Perturbations. This criterion counts differences (perturbations) between initial and the current solution. It is based on `PerturbationsCounter`.
  Version:
    CourseTT 1.2 (University Course Timetabling)
    Copyright (C) 2006 - 2011 Tomáš Müller
    muller@unitime.org
    http://muller.unitime.org
    This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version.
    This library 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 Lesser General Public License for more details.
    You should have received a copy of the GNU Lesser General Public License along with this library; if not see http://www.gnu.org/licenses/.

- - ### Nested Class Summary

    - ### Nested classes/interfaces inherited from class net.sf.cpsolver.ifs.criteria.AbstractCriterion

      `AbstractCriterion.ValueUpdateType`

  - ### Field Summary

    - ### Fields inherited from class net.sf.cpsolver.ifs.criteria.AbstractCriterion

      `iBest, iDebug, iValue, iValueUpdateType, iWeight, sDoubleFormat, sPercentFormat`

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `Perturbations()`

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method and Description
    --- | ---
    `double[]` | `getBounds()` Bounds (minimum and maximum) estimate for the value
    `double[]` | `getBounds(Collection<Lecture> variables)` Value bounds (minimum and maximum) of the criterion on a part of the problem
    `PerturbationsCounter<Lecture,Placement>` | `getPerturbationsCounter()`
    `String` | `getPlacementSelectionWeightName()`
    `double` | `getValue()` Current value of the criterion (optimization objective)
    `double` | `getValue(Collection<Lecture> variables)` Value of a part of the problem (given by the collection of variables)
    `double` | `getValue(Placement value, Set<Placement> conflicts)` Value of a proposed assignment (including hard conflicts)
    `double` | `getWeightDefault(DataProperties config)` Defines default weight (when `AbstractCriterion.getWeightName()` parameter is not present in the criterion).
    `boolean` | `init(Solver<Lecture,Placement> solver)` Notification that the model was initialized by the solver.

    - ### Methods inherited from class net.sf.cpsolver.coursett.criteria.TimetablingCriterion

      `getAbbreviation, getPlacementSelectionWeight, getPlacementSelectionWeightDefault, toString`

    - ### Methods inherited from class net.sf.cpsolver.ifs.criteria.AbstractCriterion

      `afterAssigned, afterUnassigned, beforeAssigned, beforeUnassigned, bestRestored, bestSaved, clearCache, computeBounds, constraintAdded, constraintRemoved, getBest, getInfo, getInfo, getModel, getName, getPerc, getPercRev, getWeight, getWeightedBest, getWeightedValue, getWeightedValue, getWeightedValue, getWeightName, inc, variableAdded, variableRemoved`

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait`

- - ### Constructor Detail

    - #### Perturbations

          public Perturbations()

  - ### Method Detail

    - #### getPlacementSelectionWeightName

          public String getPlacementSelectionWeightName()

      Overrides:
        `getPlacementSelectionWeightName` in class `TimetablingCriterion`

    - #### init

          public boolean init(Solver<Lecture,Placement> solver)

      Description copied from interface: `ModelListener`
      Notification that the model was initialized by the solver.
      Specified by:
        `init` in interface `ModelListener<Lecture,Placement>`
      Overrides:
        `init` in class `TimetablingCriterion`
      Parameters:
        `solver` - IFS solver

    - #### getWeightDefault

          public double getWeightDefault(DataProperties config)

      Description copied from class: `AbstractCriterion`
      Defines default weight (when `AbstractCriterion.getWeightName()` parameter is not present in the criterion).
      Overrides:
        `getWeightDefault` in class `AbstractCriterion<Lecture,Placement>`

    - #### getPerturbationsCounter

          public PerturbationsCounter<Lecture,Placement> getPerturbationsCounter()

    - #### getValue

          public double getValue(Placement value,
                                 Set<Placement> conflicts)

      Description copied from interface: `Criterion`
      Value of a proposed assignment (including hard conflicts)

    - #### getValue

          public double getValue()

      Description copied from interface: `Criterion`
      Current value of the criterion (optimization objective)
      Specified by:
        `getValue` in interface `Criterion<Lecture,Placement>`
      Overrides:
        `getValue` in class `AbstractCriterion<Lecture,Placement>`

    - #### getValue

          public double getValue(Collection<Lecture> variables)

      Description copied from interface: `Criterion`
      Value of a part of the problem (given by the collection of variables)
      Specified by:
        `getValue` in interface `Criterion<Lecture,Placement>`
      Overrides:
        `getValue` in class `AbstractCriterion<Lecture,Placement>`

    - #### getBounds

          public double[] getBounds()

      Description copied from interface: `Criterion`
      Bounds (minimum and maximum) estimate for the value
      Specified by:
        `getBounds` in interface `Criterion<Lecture,Placement>`
      Overrides:
        `getBounds` in class `AbstractCriterion<Lecture,Placement>`

    - #### getBounds

          public double[] getBounds(Collection<Lecture> variables)

      Description copied from interface: `Criterion`
      Value bounds (minimum and maximum) of the criterion on a part of the problem
      Specified by:
        `getBounds` in interface `Criterion<Lecture,Placement>`
      Overrides:
        `getBounds` in class `AbstractCriterion<Lecture,Placement>`