SteepestDescentOptimiser (PULsE 1.98 API)

java.lang.Object
- pulse.util.UpwardsNavigable
- - pulse.util.Group
  - - pulse.util.Accessible
    - - pulse.util.PropertyHolder
      - pulse.search.direction.PathOptimiser
        
        pulse.search.direction.GradientBasedOptimiser
        
        pulse.search.direction.CompositePathOptimiser
        
        pulse.search.direction.SteepestDescentOptimiser

All Implemented Interfaces:

Serializable, Descriptive, Reflexive
```
public class SteepestDescentOptimiser
extends CompositePathOptimiser
```
The simplest possible PathSolver, which assumes that the minimum direction coincides with the inverted gradient. Used in combination with the GoldenSectionSolver for increased accuracy.

See Also:

GoldenSectionOptimiser, Wikipedia page, Serialized Form

Field Summary
- Fields inherited from class pulse.search.direction.CompositePathOptimiser
  EPS, MAX_FAILED_ATTEMPTS

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`static SteepestDescentOptimiser`	`getInstance()`	This class uses a singleton pattern, meaning there is only instance of this class.
`GradientGuidedPath`	`initState(GeneralTask t)`	Creates a new `Path` instance for storing the gradient, direction, and minimum point for this `PathSolver`.
`void`	`prepare(GeneralTask task)`	Calculates the gradient value at the end of each step.
`String`	`toString()`

Methods inherited from class pulse.search.direction.CompositePathOptimiser
getLinearOptimiserDescriptor, getLinearSolver, iteration, listedTypes, setLinearSolver

Methods inherited from class pulse.search.direction.GradientBasedOptimiser
dx, getGradientResolution, getGradientStep, gradient, listedKeywords, reset, set, setGradientResolution

Methods inherited from class pulse.search.direction.PathOptimiser
compatibleWith, genericProperties, getErrorTolerance, getMaxIterations, getSolver, ignoreSiblings, setErrorTolerance, setInstance, setMaxIterations, setSolver, update

Methods inherited from class pulse.util.PropertyHolder
addListener, areDetailsHidden, data, describe, firePropertyChanged, getDescriptor, getListeners, getPrefix, initListeners, isListedNumericType, isListedParameter, numericData, parameterListChanged, removeListeners, setPrefix, updateProperties, updateProperty

Methods inherited from class pulse.util.Accessible
accessibleChildren, genericProperty, numericProperties, numericProperty, property, update

Methods inherited from class pulse.util.Group
access, children, contents, getSimpleName, subgroups

Methods inherited from class pulse.util.UpwardsNavigable
addHierarchyListener, getHierarchyListeners, getParent, identify, removeHierarchyListener, removeHierarchyListeners, setParent, specificAncestor, tellParent

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Method Detail
  - prepare
```
public void prepare(GeneralTask task)
             throws SolverException
```
    Calculates the gradient value at the end of each step.
    
    Specified by:
    
    prepare in class PathOptimiser
    
    Parameters:
    
    task - the SearchTask undergoing optimisation
    
    Throws:
    
    SolverException
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class PathOptimiser
  - getInstance
```
public static SteepestDescentOptimiser getInstance()
```
    This class uses a singleton pattern, meaning there is only instance of this class.
    
    Returns:
    
    the single (static) instance of this class
  - initState
```
public GradientGuidedPath initState(GeneralTask t)
```
    Creates a new Path instance for storing the gradient, direction, and minimum point for this PathSolver.
    
    Overrides:
    
    initState in class CompositePathOptimiser
    
    Parameters:
    
    t - the search task
    
    Returns:
    
    a Path instance