Package edu.uci.ics.jung.algorithms.util

Class IterativeProcess

  • All Implemented Interfaces:
    IterativeContext
    Direct Known Subclasses:
    AbstractRanker, EdmondsKarpMaxFlow
    public abstract class IterativeProcess
extends java.lang.Object
implements IterativeContext
    Provides basic infrastructure for iterative algorithms. Services provided include:
    • storage of current and max iteration count
    • framework for initialization, iterative evaluation, and finalization
    • test for convergence
    • etc.

    Algorithms that subclass this class are typically used in the following way: 

     FooAlgorithm foo = new FooAlgorithm(...)
 foo.setMaximumIterations(100); //set up conditions
 ...
 foo.evaluate(); //key method which initiates iterative process
 foo.getSomeResult();

    • Field Detail

      • iterations

        private int iterations
        Number of iterations performed.

      • maximumIterations

        private int maximumIterations
        Maximum allowed number of iterations.

      • desiredPrecision

        private double desiredPrecision
        Desired precision.

      • precision

        private double precision
        Achieved precision.

    • Constructor Detail

      • IterativeProcess

        public IterativeProcess()
        Generic constructor.

    • Method Detail

      • evaluate

        public void evaluate()
        Performs the iterative process. Note: this method does not return anything because Java does not allow mixing double, int, or objects

      • step

        public abstract void step()
        Evaluate the result of the current iteration.
        Specified by:
        step in interface IterativeContext

      • finalizeIterations

        protected void finalizeIterations()
        Perform eventual clean-up operations (must be implement by subclass when needed).

      • getDesiredPrecision

        public double getDesiredPrecision()
        Returns:
        the desired precision.

      • getIterations

        public int getIterations()
        Returns:
        the number of iterations performed.

      • getMaximumIterations

        public int getMaximumIterations()
        Returns:
        the maximum allowed number of iterations.

      • getPrecision

        public double getPrecision()
        Returns:
        the attained precision.

      • setPrecision

        public void setPrecision​(double precision)
        Parameters:
        precision - the precision to set

      • hasConverged

        public boolean hasConverged()
        Check to see if the result has been attained.
        Returns:
        boolean

      • done

        public boolean done()
        Specified by:
        done in interface IterativeContext
        Returns:
        true if this iterative process is finished, and false otherwise.

      • initializeIterations

        protected void initializeIterations()
        Initializes internal parameters to start the iterative process.

      • reset

        public void reset()

      • relativePrecision

        public double relativePrecision​(double epsilon,
                                double x)
        Parameters:
        epsilon - double
        x - double
        Returns:
        double

      • setDesiredPrecision

        public void setDesiredPrecision​(double prec)
                         throws java.lang.IllegalArgumentException
        Parameters:
        prec - the desired precision.
        Throws:
        java.lang.IllegalArgumentException

      • setMaximumIterations

        public void setMaximumIterations​(int maxIter)
                          throws java.lang.IllegalArgumentException
        Parameters:
        maxIter - the maximum allowed number of iterations
        Throws:
        java.lang.IllegalArgumentException