//
//  Copyright (C) 2003-2007 Rational Discovery LLC
//
//  @@ All Rights Reserved @@
//  This file is part of the RDKit.
//  The contents are covered by the terms of the BSD license
//  which is included in the file license.txt, found at the root
//  of the RDKit source tree.
//
#include <RDGeneral/export.h>
#ifndef __RD_METRICFUNCS_H__
#define __RD_METRICFUNCS_H__
#include <cmath>
#include <DataStructs/BitOps.h>
#include <RDGeneral/Invariant.h>

namespace RDDataManip {
//! return the Euclidean distance between two vectors
template <typename T1, typename T2>
double EuclideanDistanceMetric(const T1 &v1, const T2 &v2, unsigned int dim) {
  double dist = 0.0;
  for (unsigned int i = 0; i < dim; i++) {
    double diff = static_cast<double>(v1[i]) - static_cast<double>(v2[i]);
    dist += (diff * diff);
  }
  return sqrt(dist);
};

// FIX: there's no reason to have this tied to TanimotoSimilarity... could
// include
// a different sim function as a template param
//! return the Tanimoto distance (1-TanimotoSimilarity) between two bit vectors
template <typename T1, typename T2>
double TanimotoDistanceMetric(const T1 &bv1, const T2 &bv2, unsigned int dim) {
  // the dim parameter is actually irrelevant here but we have to include it to
  // deal with
  // template version of setMetricFunc in MetricMatricCalc
  RDUNUSED_PARAM(dim);
  return (1.0 - SimilarityWrapper(
                    bv1, bv2,
                    (double (*)(const T1 &, const T2 &))TanimotoSimilarity));
};

//! return the Tanimoto similarity between two bit vectors
template <typename T1, typename T2>
double TanimotoSimilarityMetric(const T1 &bv1, const T2 &bv2,
                                unsigned int dim) {
  RDUNUSED_PARAM(dim);
  return SimilarityWrapper(
      bv1, bv2, (double (*)(const T1 &, const T2 &))TanimotoSimilarity);
};
}  // namespace RDDataManip

#endif