SupportVectorReductionTKernel, TInput Class |
Namespace: Accord.MachineLearning.VectorMachines.Learning
public class SupportVectorReduction<TKernel, TInput> : SupportVectorReductionBase<SupportVectorMachine<TKernel, TInput>, TKernel, TInput> where TKernel : Object, IKernel<TInput> where TInput : ICloneable
The SupportVectorReductionTKernel, TInput type exposes the following members.
Name | Description | |
---|---|---|
SupportVectorReductionTKernel, TInput |
Initializes a new instance of the SupportVectorReduction class.
|
Name | Description | |
---|---|---|
Input |
Gets or sets the input vectors for training.
(Inherited from BaseSupportVectorCalibrationTModel, TKernel, TInput.) | |
IsLinear |
Gets whether the machine being learned is linear.
(Inherited from BaseSupportVectorCalibrationTModel, TKernel, TInput.) | |
Kernel |
Gets the machine's IKernel function.
(Inherited from BaseSupportVectorCalibrationTModel, TKernel, TInput.) | |
Model |
Gets the machine to be taught.
(Inherited from BaseSupportVectorCalibrationTModel, TKernel, TInput.) | |
Output |
Gets or sets the output labels for each training vector.
(Inherited from BaseSupportVectorCalibrationTModel, TKernel, TInput.) | |
Threshold |
Gets or sets the minimum threshold that is used to determine
whether a weight will be kept in the machine or not. Default
is 1e-12.
(Inherited from SupportVectorReductionBaseTModel, TKernel, TInput.) | |
Token |
Gets or sets a cancellation token that can be used to
stop the learning algorithm while it is running.
(Inherited from BaseSupportVectorCalibrationTModel, TKernel, TInput.) |
Name | Description | |
---|---|---|
Create |
Creates an instance of the model to be learned. Inheritors
of this abstract class must define this method so new models
can be created from the training data.
(Inherited from BaseSupportVectorCalibrationTModel, TKernel, TInput.) | |
Equals | Determines whether the specified object is equal to the current object. (Inherited from Object.) | |
Finalize | Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.) | |
GetHashCode | Serves as the default hash function. (Inherited from Object.) | |
GetType | Gets the Type of the current instance. (Inherited from Object.) | |
InnerRun |
Runs the learning algorithm.
(Inherited from SupportVectorReductionBaseTModel, TKernel, TInput.) | |
Learn |
Learns a model that can map the given inputs to the given outputs.
(Inherited from SupportVectorReductionBaseTModel, TKernel, TInput.) | |
Learn(TInput, Boolean, Double) |
Learns a model that can map the given inputs to the given outputs.
(Inherited from BaseSupportVectorCalibrationTModel, TKernel, TInput.) | |
Learn(TInput, Boolean, Double) |
Learns a model that can map the given inputs to the given outputs.
(Inherited from BaseSupportVectorCalibrationTModel, TKernel, TInput.) | |
Learn(TInput, Double, Double) |
Learns a model that can map the given inputs to the given outputs.
(Inherited from BaseSupportVectorCalibrationTModel, TKernel, TInput.) | |
Learn(TInput, Int32, Double) |
Learns a model that can map the given inputs to the given outputs.
(Inherited from BaseSupportVectorCalibrationTModel, TKernel, TInput.) | |
Learn(TInput, Int32, Double) |
Learns a model that can map the given inputs to the given outputs.
(Inherited from BaseSupportVectorCalibrationTModel, TKernel, TInput.) | |
MemberwiseClone | Creates a shallow copy of the current Object. (Inherited from Object.) | |
Run | Obsolete.
Obsolete.
(Inherited from SupportVectorReductionBaseTModel, TKernel, TInput.) | |
ToString | Returns a string that represents the current object. (Inherited from Object.) |
Name | Description | |
---|---|---|
HasMethod |
Checks whether an object implements a method with the given name.
(Defined by ExtensionMethods.) | |
IsEqual |
Compares two objects for equality, performing an elementwise
comparison if the elements are vectors or matrices.
(Defined by Matrix.) | |
To(Type) | Overloaded.
Converts an object into another type, irrespective of whether
the conversion can be done at compile time or not. This can be
used to convert generic types to numeric types during runtime.
(Defined by ExtensionMethods.) | |
ToT | Overloaded.
Converts an object into another type, irrespective of whether
the conversion can be done at compile time or not. This can be
used to convert generic types to numeric types during runtime.
(Defined by ExtensionMethods.) |
The following example shows how to reduce the number of support vectors in a SVM by removing vectors which are linearly dependent between themselves.
// Example AND problem double[][] inputs = { new double[] { 0, 0 }, // 0 and 0: 0 (label -1) new double[] { 0, 1 }, // 0 and 1: 0 (label -1) new double[] { 1, 0 }, // 1 and 0: 0 (label -1) new double[] { 1, 1 } // 1 and 1: 1 (label +1) }; // Dichotomy SVM outputs should be given as [-1;+1] int[] labels = { // 0, 0, 0, 1 -1, -1, -1, 1 }; // Instantiate a new learning algorithm for SVMs var smo = new SequentialMinimalOptimization<Linear>() { // Set up the learning algorithm Complexity = 100.0 }; // Run var svm = smo.Learn(inputs, labels); int numberBefore = svm.SupportVectors.Length; // should be double errorBefore = new ZeroOneLoss(labels).Loss(svm.Decide(inputs)); // should be 0 // At this point we have the weighted support vectors // w sv b // (+4) * (1,1) -3 // (-2) * (1,0) // (-2) * (0,1) // // However, it can be seen that the last SV can be written // as a linear combination of the two first vectors: // // (0,1) = (1,1) - (1,0) // // Since we have a linear space (we are using a linear kernel) // this vector could be removed from the support vector set. // // f(x) = sum(alpha_i * x * x_i) + b // = 4*(1,1)*x - 2*(1,0)*x - 2*(0,1)*x - 3 // = 4*(1,1)*x - 2*(1,0)*x - 2*((1,1) - (1,0))*x - 3 // = 4*(1,1)*x - 2*(1,0)*x - 2*(1,1)*x + 2*(1,0)*x - 3 // = 4*(1,1)*x - 2*(1,0)*x - 2*(1,1)*x + 2*(1,0)*x - 3 // = 2*(1,1)*x - 3 // = 2*x1 + 2*x2 - 3 // // Clone the original machine so we don't change it var clone = (SupportVectorMachine<Linear>)svm.Clone(); // Create a support vector reduction algorithm var svr = new SupportVectorReduction<Linear>(clone); // Reduce the number of support vectors var svm2 = svr.Learn(); int numberAfter = svm2.SupportVectors.Length; // should be 1 // Compute the new error double errorAfter = new ZeroOneLoss(labels).Loss(svm2.Decide(inputs)); // should still be 0