NearestNeighborInterpolator.h

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/*
 * Copyright (C) 2012 by
 *   MetraLabs GmbH (MLAB), GERMANY
 * and
 *   Neuroinformatics and Cognitive Robotics Labs (NICR) at TU Ilmenau, GERMANY
 * All rights reserved.
 *
 * Contact: info@mira-project.org
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 *   packaging of this file. Please review the following information to
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#ifndef _MIRA_NEARESTNEIGHBORINTERPOLATOR_H__
#define _MIRA_NEARESTNEIGHBORINTERPOLATOR_H__

#include <assert.h>

#include <math/IntervalFilter.h>

namespace mira {


class NearestNeighborInterpolator : public IntervalFilter
{
public:
    bool canExtrapolate() const { return true; }
    int samples() const         { return 2; }
    int samplesBefore() const   { return 1; }
    int samplesAfter() const    { return 1; }

    template <typename Tx, typename Ty, typename ContainerTx, typename ContainerTy>
    const Ty& apply(const ContainerTx& x, const ContainerTy& y, const Tx& xx)
    {
        assert(x.size()==2);
        assert(x.size()==y.size());

        // catch extrapolation cases
        if(xx <= x.front())
            return y.front();

        if(xx >= x.back())
            return y.back();

        // find the closet point of the two points
        if(xx-x.front() < x.back()-xx)
            return y.front();
        else
            return y.back();
    }
};


} // namespace

#endif /* _MIRA_NEARESTNEIGHBORINTERPOLATOR_H_ */