BacktrackingLineSearch (ImgLib2 Javadocs 0-SNAPSHOT API)

java.lang.Object
- net.imglib2.realtransform.inverse.BacktrackingLineSearch

```
public class BacktrackingLineSearch
extends Object
```
A generic backtracking line search to iteratively estimate the inverse of a RealTransform. This should never be used when a closed-form inverse is available.

Author:

John Bogovic

Field Summary

Fields
Modifier and Type Field and Description

protected static org.slf4j.Logger logger

Fields
Modifier and Type	Field and Description
`protected static org.slf4j.Logger`	`logger`

Constructor Summary

Constructors
Constructor and Description

BacktrackingLineSearch(DifferentiableRealTransform fwdXfm)

BacktrackingLineSearch(int nd)

Constructors
Constructor and Description
`BacktrackingLineSearch(DifferentiableRealTransform fwdXfm)`
`BacktrackingLineSearch(int nd)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`double`	`backtrackingLineSearch(double c, double beta, int maxtries, double t0)` Perform backtracking line search.
`double`	`dirMag()`
`double`	`getLastError()`
`double`	`getLastSquaredError()`
`double`	`iterativeInverse(double[] source, double[] destination)` Find the source point that, when pushed through the forward transform, results in the given destination point.
`void`	`setBeta(double beta)`
`void`	`setC(double c)`
`void`	`setDirection(double[] dir)`
`void`	`setEpsilon(double eps)`
`void`	`setEstimate(double[] est)`
`void`	`setForwardTransform(DifferentiableRealTransform fwdXfm)`
`void`	`setInitStep(double initStepSize)`
`void`	`setMaxIterations(int maxIters)`
`void`	`setMaxLineSearchTries(int lineSearchMaxTries)`
`void`	`setTarget(double[] tgt)`
`double`	`squaredError(double[] estimate)` Compute the squared error between this estimate and the target.
`double`	`squaredErrorAt(double[] source)` Compute the squared error between the destination of the input source point and the target.

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

- Field Detail
  - logger
```
protected static org.slf4j.Logger logger
```
- Constructor Detail
  - BacktrackingLineSearch
```
public BacktrackingLineSearch(int nd)
```
  - BacktrackingLineSearch
```
public BacktrackingLineSearch(DifferentiableRealTransform fwdXfm)
```
- Method Detail
  - setForwardTransform
```
public void setForwardTransform(DifferentiableRealTransform fwdXfm)
```
  - setC
```
public void setC(double c)
```
  - setBeta
```
public void setBeta(double beta)
```
  - setInitStep
```
public void setInitStep(double initStepSize)
```
  - setMaxIterations
```
public void setMaxIterations(int maxIters)
```
  - setMaxLineSearchTries
```
public void setMaxLineSearchTries(int lineSearchMaxTries)
```
  - setEpsilon
```
public void setEpsilon(double eps)
```
  - setEstimate
```
public void setEstimate(double[] est)
```
  - setTarget
```
public void setTarget(double[] tgt)
```
  - setDirection
```
public void setDirection(double[] dir)
```
  - squaredError
```
public double squaredError(double[] estimate)
```
    Compute the squared error between this estimate and the target.
    
    Parameters:
    
    estimate - the current estimate
    
    Returns:
    
    the squared error
  - squaredErrorAt
```
public double squaredErrorAt(double[] source)
```
    Compute the squared error between the destination of the input source point and the target.
    
    Parameters:
    
    source - the current source
    
    Returns:
    
    the squared error
  - dirMag
```
public double dirMag()
```
  - backtrackingLineSearch
```
public double backtrackingLineSearch(double c,
                                     double beta,
                                     int maxtries,
                                     double t0)
```
    Perform backtracking line search.
    
    Parameters:
    
    c - the armijoCondition parameter
    
    beta - the fraction to multiply the step size at each iteration ( < 1 )
    
    maxtries - max number of tries
    
    t0 - initial step size
    
    Returns:
    
    the step size
  - iterativeInverse
```
public double iterativeInverse(double[] source,
                               double[] destination)
```
    Find the source point that, when pushed through the forward transform, results in the given destination point. Iteratively estimates the result with backtracking line search.
    Terminates either when a maximum iteration count has been reached, or the error falls below a specified threshold.
    
    Parameters:
    
    source - the source point that will be overwritten
    
    destination - the destination point
    
    Returns:
    
    error of inverse
  - getLastSquaredError
```
public double getLastSquaredError()
```
  - getLastError
```
public double getLastError()
```

Class BacktrackingLineSearch

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

logger

Constructor Detail

BacktrackingLineSearch

BacktrackingLineSearch

Method Detail

setForwardTransform

setC

setBeta

setInitStep

setMaxIterations

setMaxLineSearchTries

setEpsilon

setEstimate

setTarget

setDirection

squaredError

squaredErrorAt

dirMag

backtrackingLineSearch

iterativeInverse

getLastSquaredError

getLastError