JulierUnscentedTransform (Hipparchus 3.0 API)

java.lang.Object
- org.hipparchus.util.AbstractUnscentedTransform
- - org.hipparchus.util.JulierUnscentedTransform

All Implemented Interfaces:

UnscentedTransformProvider
```
public class JulierUnscentedTransform
extends AbstractUnscentedTransform
```
Unscented transform as defined by Julier and Uhlmann.
The unscented transform uses three parameters: alpha, beta and kappa. Alpha determines the spread of the sigma points around the process state, kappa is a secondary scaling parameter, and beta is used to incorporate prior knowledge of the distribution of the process state.
The Julier transform is a particular case of MerweUnscentedTransform with alpha = 1 and beta = 0.

Since:

2.2

See Also:

"S. J. Julier and J. K. Uhlmann. A New Extension of the Kalman Filter to Nonlinear Systems. Proc. SPIE 3068, Signal Processing, Sensor Fusion, and Target Recognition VI, 182 (July 28, 1997)"

Field Summary

Fields
Modifier and Type Field Description

static double DEFAULT_KAPPA
Default value for kappa, (0.0, see reference).

Constructor Summary

Constructors
Constructor	Description
`JulierUnscentedTransform(int stateDim)`	Default constructor.
`JulierUnscentedTransform(int stateDim, double kappa)`	Simple constructor.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`protected double`	`getMultiplicationFactor()`	Get the factor applied to the covariance matrix during the unscented transform.
`RealVector`	`getWc()`	Get the covariance weights.
`RealVector`	`getWm()`	Get the mean weights.

Methods inherited from class org.hipparchus.util.AbstractUnscentedTransform
unscentedTransform

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

- Field Detail
  - DEFAULT_KAPPA
```
public static final double DEFAULT_KAPPA
```
    Default value for kappa, (0.0, see reference).
    
    See Also:
    
    Constant Field Values
- Constructor Detail
  - JulierUnscentedTransform
```
public JulierUnscentedTransform(int stateDim)
```
    Default constructor.
    This constructor uses default value for kappa.
    
    Parameters:
    
    stateDim - the dimension of the state
    
    See Also:
    
    DEFAULT_KAPPA, JulierUnscentedTransform(int, double)
  - JulierUnscentedTransform
```
public JulierUnscentedTransform(int stateDim,
                                double kappa)
```
    Simple constructor.
    
    Parameters:
    
    stateDim - the dimension of the state
    
    kappa - fscaling factor
- Method Detail
  - getWc
```
public RealVector getWc()
```
    Get the covariance weights.
    
    Returns:
    
    the covariance weights
  - getWm
```
public RealVector getWm()
```
    Get the mean weights.
    
    Returns:
    
    the mean weights
  - getMultiplicationFactor
```
protected double getMultiplicationFactor()
```
    Get the factor applied to the covariance matrix during the unscented transform.
    
    Specified by:
    
    getMultiplicationFactor in class AbstractUnscentedTransform
    
    Returns:
    
    the factor applied to the covariance matrix during the unscented transform