drwnFeatureWhitener.h

/******************************************************************************
** DARWIN: A FRAMEWORK FOR MACHINE LEARNING RESEARCH AND DEVELOPMENT
** Distributed under the terms of the BSD license (see the LICENSE file)
** Copyright (c) 2007-2015, Stephen Gould
** All rights reserved.
**
******************************************************************************
** FILENAME:    drwnFeatureWhitener.h
** AUTHOR(S):   Stephen Gould <stephen.gould@anu.edu.au>
**
*****************************************************************************/

#pragma once

#include <vector>
#include <limits>

#include "Eigen/Core"

#include "drwnBase.h"
#include "drwnFeatureTransform.h"
#include "drwnSuffStats.h"

using namespace std;
using namespace Eigen;

// drwnFeatureWhitener class --------------------------------------------------

class drwnFeatureWhitener : public drwnUnsupervisedTransform {
 private:
    VectorXd _mu;       
    VectorXd _beta;     

 public:
    drwnFeatureWhitener();
    drwnFeatureWhitener(const drwnSuffStats& stats);
    drwnFeatureWhitener(const drwnFeatureWhitener& fw);
    ~drwnFeatureWhitener();

    // access functions
    const char *type() const { return "drwnFeatureWhitener"; }
    drwnFeatureWhitener *clone() const { return new drwnFeatureWhitener(*this); }

    // i/o
    void clear();
    bool save(drwnXMLNode& node) const;
    bool load(drwnXMLNode& node);

    // training
    using drwnUnsupervisedTransform::train;
    double train(const drwnSuffStats& stats);
    double train(const vector<vector<double> >& features);

    // evaluation
    using drwnFeatureTransform::transform;
    void transform(vector<double>& x) const;
    void transform(const vector<double>& x, vector<double>& y) const;
};