Package smile.base.svm

Class KernelMachine<T>

java.lang.Object

smile.base.svm.KernelMachine<T>

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

KernelMachine, SVM, SVM

public class KernelMachine<T>
extends Object
implements Serializable

Kernel machines. Kernel methods owe their name to the use of kernel functions, which enable them to operate in a high-dimensional, implicit feature space without ever computing the coordinates of the data in that space, but rather by simply computing the inner products between the images of all pairs of data in the feature space.

Kernel methods can be thought of as instance-based learners: rather than learning some fixed set of parameters corresponding to the features of their inputs, they instead store (a subset of) their training set (or a new representation) and learn for it a corresponding weight. Prediction for unlabeled inputs is treated by the application of a similarity function.

See Also:

• Serialized Form

Constructor Summary

Constructors

Constructor	Description
KernelMachine(MercerKernel<T> kernel, T[] vectors, double[] weight)	Constructor.
KernelMachine(MercerKernel<T> kernel, T[] vectors, double[] weight, double b)	Constructor.

Method Summary

Modifier and Type	Method	Description
double	intercept()	Returns the intercept.
MercerKernel<T>	kernel()	Returns the kernel function.
double	score(T x)	Returns the decision function value.
String	toString()
T[]	vectors()	Returns the support vectors of kernel machines.
double[]	weights()	Returns the weights of instances.

Methods inherited from class java.lang.Object

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

Constructor Details

KernelMachine

public KernelMachine(MercerKernel<T> kernel,
 T[] vectors,
 double[] weight)

Constructor.

Parameters:

kernel - Kernel function.

vectors - The instances in the kernel machine, e.g. support vectors.

weight - The weights of instances.

KernelMachine

public KernelMachine(MercerKernel<T> kernel,
 T[] vectors,
 double[] weight,
 double b)

Constructor.

Parameters:

kernel - Kernel function.

vectors - The instances in the kernel machine, e.g. support vectors.

weight - The weights of instances.

b - The intercept;

Method Details

kernel

public MercerKernel<T> kernel()

Returns the kernel function.

Returns:

the kernel function.

vectors

public T[] vectors()

Returns the support vectors of kernel machines.

Returns:

the support vectors of kernel machines.

weights

public double[] weights()

Returns the weights of instances.

Returns:

the weights of instances.

intercept

public double intercept()

Returns the intercept.

Returns:

the intercept.

score

public double score(T x)

Returns the decision function value.

Parameters:

x - an instance.

Returns:

the decision function value.

toString

public String toString()

Overrides:

toString in class Object