drwnLinearTransform.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:    drwnLinearTransform.h
** AUTHOR(S):   Stephen Gould <stephen.gould@anu.edu.au>
**              Jiecheng Zhao <u5143437@anu.edu.au>
**
*****************************************************************************/

#pragma once

#include <vector>
#include <limits>

#include "Eigen/Core"

#include "drwnBase.h"
#include "drwnML.h"

using namespace std;
using namespace Eigen;

// drwnLinearTransform class ------------------------------------------------------

class drwnLinearTransform : public drwnFeatureTransform {
 private:
    VectorXd _mu;             
    MatrixXd _projection;     

 public:
    drwnLinearTransform();
    drwnLinearTransform(const VectorXd& mu, const MatrixXd& projection);
    drwnLinearTransform(const drwnLinearTransform& xform);
    ~drwnLinearTransform();

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

    void set(const VectorXd& mu, const MatrixXd& projection);
    void set(const MatrixXd& projection);
    const VectorXd &translation() const { return _mu; }
    const MatrixXd &projection() const { return _projection; }

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

    // input/output size
    int numInputs() const { return _projection.cols(); }
    int numOutputs() const { return _projection.rows(); }

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