Negation.h
1 /* This file is part of the Gudhi Library - https://gudhi.inria.fr/ - which is released under MIT.
2  * See file LICENSE or go to https://gudhi.inria.fr/licensing/ for full license details.
3  * Author(s): Siargey Kachanovich
4  *
5  * Copyright (C) 2019 Inria
6  *
7  * Modification(s):
8  * - YYYY/MM Author: Description of the modification
9  */
10 
11 #ifndef FUNCTIONS_NEGATION_H_
12 #define FUNCTIONS_NEGATION_H_
13 
14 #include <cstdlib> // for std::size_t
15 
16 #include <Eigen/Dense>
17 
18 namespace Gudhi {
19 
20 namespace coxeter_triangulation {
21 
30 template <class Function_>
31 struct Negation {
36  Eigen::VectorXd operator()(const Eigen::VectorXd& p) const {
37  Eigen::VectorXd result = -fun_(p);
38  return result;
39  }
40 
42  std::size_t amb_d() const { return fun_.amb_d(); }
43 
45  std::size_t cod_d() const { return fun_.cod_d(); }
46 
48  Eigen::VectorXd seed() const {
49  Eigen::VectorXd result = fun_.seed();
50  return result;
51  }
52 
58  Negation(const Function_& function) : fun_(function) {}
59 
60  private:
61  Function_ fun_;
62 };
63 
75 template <class Function_>
76 Negation<Function_> negation(const Function_& function) {
77  return Negation<Function_>(function);
78 }
79 
80 } // namespace coxeter_triangulation
81 
82 } // namespace Gudhi
83 
84 #endif
Negation< Function_ > negation(const Function_ &function)
Static constructor of the negative function.
Definition: Negation.h:76
Gudhi namespace.
Definition: SimplicialComplexForAlpha.h:14
Constructs the "minus" function. The zero-set is the same, but the values at other points are the neg...
Definition: Negation.h:31
Eigen::VectorXd operator()(const Eigen::VectorXd &p) const
Value of the function at a specified point.
Definition: Negation.h:36
Negation(const Function_ &function)
Constructor of the negative function.
Definition: Negation.h:58
std::size_t cod_d() const
Returns the codomain dimension.
Definition: Negation.h:45
std::size_t amb_d() const
Returns the domain (ambient) dimension.
Definition: Negation.h:42
Eigen::VectorXd seed() const
Returns a point on the zero-set.
Definition: Negation.h:48