Package org.apache.commons.math4.linear

Class IterativeLinearSolverEvent

java.lang.Object
java.util.EventObject
org.apache.commons.math4.util.IterationEvent
org.apache.commons.math4.linear.IterativeLinearSolverEvent
All Implemented Interfaces:
java.io.Serializable
Direct Known Subclasses:
DefaultIterativeLinearSolverEvent
public abstract class IterativeLinearSolverEvent
extends IterationEvent
This is the base class for all events occurring during the iterations of a IterativeLinearSolver.
Since:
3.0
See Also:
Serialized Form

  • Field Summary

    Fields inherited from class java.util.EventObject

    source

  • Constructor Summary

    Constructors 
    Constructor Description
    IterativeLinearSolverEvent​(java.lang.Object source, int iterations)
    Creates a new instance of this class.

  • Method Summary

    Modifier and Type Method Description
    abstract double getNormOfResidual()
    Returns the norm of the residual.
    RealVector getResidual()
    Returns the residual.
    abstract RealVector getRightHandSideVector()
    Returns the current right-hand side of the linear system to be solved.
    abstract RealVector getSolution()
    Returns the current estimate of the solution to the linear system to be solved.
    boolean providesResidual()
    Returns true if getResidual() is supported.

    Methods inherited from class org.apache.commons.math4.util.IterationEvent

    getIterations

    Methods inherited from class java.util.EventObject

    getSource, toString

    Methods inherited from class java.lang.Object

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

  • Constructor Details

    • IterativeLinearSolverEvent

      public IterativeLinearSolverEvent​(java.lang.Object source, int iterations)
      Creates a new instance of this class.
      Parameters:
      source - the iterative algorithm on which the event initially occurred
      iterations - the number of iterations performed at the time this event is created

  • Method Details

    • getRightHandSideVector

      public abstract RealVector getRightHandSideVector()
      Returns the current right-hand side of the linear system to be solved. This method should return an unmodifiable view, or a deep copy of the actual right-hand side vector, in order not to compromise subsequent iterations of the source IterativeLinearSolver.
      Returns:
      the right-hand side vector, b

    • getNormOfResidual

      public abstract double getNormOfResidual()
      Returns the norm of the residual. The returned value is not required to be exact. Instead, the norm of the so-called updated residual (if available) should be returned. For example, the conjugate gradient method computes a sequence of residuals, the norm of which is cheap to compute. However, due to accumulation of round-off errors, this residual might differ from the true residual after some iterations. See e.g. A. Greenbaum and Z. Strakos, Predicting the Behavior of Finite Precision Lanzos and Conjugate Gradient Computations, Technical Report 538, Department of Computer Science, New York University, 1991 (available here).
      Returns:
      the norm of the residual, ||r||

    • getResidual

      public RealVector getResidual()

      Returns the residual. This is an optional operation, as all iterative linear solvers do not provide cheap estimate of the updated residual vector, in which case

      The default implementation throws a MathUnsupportedOperationException. If this method is overriden, then providesResidual() should be overriden as well.

      Returns:
      the updated residual, r

    • getSolution

      public abstract RealVector getSolution()
      Returns the current estimate of the solution to the linear system to be solved. This method should return an unmodifiable view, or a deep copy of the actual current solution, in order not to compromise subsequent iterations of the source IterativeLinearSolver.
      Returns:
      the solution, x

    • providesResidual

      public boolean providesResidual()
      Returns true if getResidual() is supported. The default implementation returns false.
      Returns:
      false if getResidual() throws a MathUnsupportedOperationException