RDKit
Open-source cheminformatics and machine learning.
Ranking.h
Go to the documentation of this file.
1 //
2 // Copyright (C) 2004-2015 Greg Landrum and Rational Discovery LLC
3 //
4 // @@ All Rights Reserved @@
5 // This file is part of the RDKit.
6 // The contents are covered by the terms of the BSD license
7 // which is included in the file license.txt, found at the root
8 // of the RDKit source tree.
9 //
10 
11 //! \file Ranking.h
12 /*!
13  \brief Utility functionality used to rank sequences
14 
15  Much of this used to be in GraphMol/RankAtoms.h
16 */
17 #include <RDGeneral/export.h>
18 #ifndef RD_RANKING_H
19 #define RD_RANKING_H
20 
21 #include <vector>
22 #include <functional>
23 #include <algorithm>
24 #include <cstdint>
25 
26 namespace Rankers {
27 inline auto pairGreater = [](const auto &v1, const auto &v2) {
28  return v1.first > v2.first;
29 };
30 
31 //! function for implementing < on two std::pairs. The first entries are
32 /// compared.
33 inline auto pairLess = [](const auto &v1, const auto &v2) {
34  return v1.first < v2.first;
35 };
36 
37 //! ranks the entries in a vector
38 /*!
39  \param vect the vector to rank
40  \param res is used to return the ranks of each entry
41 */
42 template <typename T1, typename T2>
43 void rankVect(const std::vector<T1> &vect, T2 &res) {
44  PRECONDITION(res.size() >= vect.size(), "vector size mismatch");
45  unsigned int nEntries = rdcast<unsigned int>(vect.size());
46 
47  std::vector<unsigned int> indices(nEntries);
48  for (unsigned int i = 0; i < nEntries; ++i) {
49  indices[i] = i;
50  }
51  std::sort(indices.begin(), indices.end(),
52  [&](auto i1, auto i2) { return vect[i1] < vect[i2]; });
53 
54  int currRank = 0;
55  unsigned int lastIdx = indices[0];
56  for (auto idx : indices) {
57  if (vect[idx] == vect[lastIdx]) {
58  res[idx] = currRank;
59  } else {
60  res[idx] = ++currRank;
61  lastIdx = idx;
62  }
63  }
64 }
65 } // namespace Rankers
66 #endif
#define PRECONDITION(expr, mess)
Definition: Invariant.h:109
Utility functionality used to rank sequences.
Definition: Ranking.h:26
auto pairGreater
Definition: Ranking.h:27
void rankVect(const std::vector< T1 > &vect, T2 &res)
ranks the entries in a vector
Definition: Ranking.h:43
auto pairLess
Definition: Ranking.h:33