Package org.apache.commons.math4.neuralnet.twod

Class NeuronSquareMesh2D.DataVisualization

java.lang.Object

org.apache.commons.math4.neuralnet.twod.NeuronSquareMesh2D.DataVisualization

Enclosing class:

NeuronSquareMesh2D

public static final class NeuronSquareMesh2D.DataVisualization
extends Object

Miscellaneous indicators of the map quality.

• Hit histogram
• Quantization error
• Topographic error
• Unified distance matrix

Method Summary

Modifier and Type	Method	Description
double	getMeanQuantizationError()
double	getMeanTopographicError()
double[][]	getNormalizedHits()
int	getNumberOfSamples()
double[][]	getQuantizationError()
double[][]	getTopographicError()
double[][]	getUMatrix()

Methods inherited from class java.lang.Object

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

Method Detail

getNumberOfSamples

public int getNumberOfSamples()

Returns:

the total number of samples.

getQuantizationError

public double[][] getQuantizationError()

Returns:

the quantization error. Each bin will contain the average of the distances between samples mapped to the corresponding unit and the weight vector of that unit.

See Also:

getMeanQuantizationError()

getTopographicError

public double[][] getTopographicError()

Returns:

the topographic error. Each bin will contain the number of data for which the first and second best matching units are not adjacent in the map.

See Also:

getMeanTopographicError()

getNormalizedHits

public double[][] getNormalizedHits()

Returns:

the hits histogram (normalized). Each bin will contain the number of data for which the corresponding neuron is the best matching unit.

getUMatrix

public double[][] getUMatrix()

Returns:

the U-matrix. Each bin will contain the average distance between a unit and all its neighbours will be computed (and stored in the pixel corresponding to that unit of the 2D-map). The number of neighbours taken into account depends on the network neighbourhood type.

getMeanQuantizationError

public double getMeanQuantizationError()

Returns:

the mean (hit-weighted) quantization error.

See Also:

getQuantizationError()

getMeanTopographicError

public double getMeanTopographicError()

Returns:

the mean (hit-weighted) topographic error.

See Also:

getTopographicError()