1 // This file is part of Eigen, a lightweight C++ template library
2 // for linear algebra.
3 //
4 // Copyright (C) 2009 Thomas Capricelli <orzel@freehackers.org>
5 
6 #include <stdio.h>
7 
8 #include "main.h"
9 #include <unsupported/Eigen/NumericalDiff>
10 
11 // Generic functor
12 template<typename _Scalar, int NX=Dynamic, int NY=Dynamic>
13 struct Functor
14 {
15   typedef _Scalar Scalar;
16   enum {
17     InputsAtCompileTime = NX,
18     ValuesAtCompileTime = NY
19   };
20   typedef Matrix<Scalar,InputsAtCompileTime,1> InputType;
21   typedef Matrix<Scalar,ValuesAtCompileTime,1> ValueType;
22   typedef Matrix<Scalar,ValuesAtCompileTime,InputsAtCompileTime> JacobianType;
23 
24   int m_inputs, m_values;
25 
FunctorFunctor26   Functor() : m_inputs(InputsAtCompileTime), m_values(ValuesAtCompileTime) {}
FunctorFunctor27   Functor(int inputs, int values) : m_inputs(inputs), m_values(values) {}
28 
inputsFunctor29   int inputs() const { return m_inputs; }
valuesFunctor30   int values() const { return m_values; }
31 
32 };
33 
34 struct my_functor : Functor<double>
35 {
my_functormy_functor36     my_functor(void): Functor<double>(3,15) {}
operator ()my_functor37     int operator()(const VectorXd &x, VectorXd &fvec) const
38     {
39         double tmp1, tmp2, tmp3;
40         double y[15] = {1.4e-1, 1.8e-1, 2.2e-1, 2.5e-1, 2.9e-1, 3.2e-1, 3.5e-1,
41             3.9e-1, 3.7e-1, 5.8e-1, 7.3e-1, 9.6e-1, 1.34, 2.1, 4.39};
42 
43         for (int i = 0; i < values(); i++)
44         {
45             tmp1 = i+1;
46             tmp2 = 16 - i - 1;
47             tmp3 = (i>=8)? tmp2 : tmp1;
48             fvec[i] = y[i] - (x[0] + tmp1/(x[1]*tmp2 + x[2]*tmp3));
49         }
50         return 0;
51     }
52 
actual_dfmy_functor53     int actual_df(const VectorXd &x, MatrixXd &fjac) const
54     {
55         double tmp1, tmp2, tmp3, tmp4;
56         for (int i = 0; i < values(); i++)
57         {
58             tmp1 = i+1;
59             tmp2 = 16 - i - 1;
60             tmp3 = (i>=8)? tmp2 : tmp1;
61             tmp4 = (x[1]*tmp2 + x[2]*tmp3); tmp4 = tmp4*tmp4;
62             fjac(i,0) = -1;
63             fjac(i,1) = tmp1*tmp2/tmp4;
64             fjac(i,2) = tmp1*tmp3/tmp4;
65         }
66         return 0;
67     }
68 };
69 
test_forward()70 void test_forward()
71 {
72     VectorXd x(3);
73     MatrixXd jac(15,3);
74     MatrixXd actual_jac(15,3);
75     my_functor functor;
76 
77     x << 0.082, 1.13, 2.35;
78 
79     // real one
80     functor.actual_df(x, actual_jac);
81 //    std::cout << actual_jac << std::endl << std::endl;
82 
83     // using NumericalDiff
84     NumericalDiff<my_functor> numDiff(functor);
85     numDiff.df(x, jac);
86 //    std::cout << jac << std::endl;
87 
88     VERIFY_IS_APPROX(jac, actual_jac);
89 }
90 
test_central()91 void test_central()
92 {
93     VectorXd x(3);
94     MatrixXd jac(15,3);
95     MatrixXd actual_jac(15,3);
96     my_functor functor;
97 
98     x << 0.082, 1.13, 2.35;
99 
100     // real one
101     functor.actual_df(x, actual_jac);
102 
103     // using NumericalDiff
104     NumericalDiff<my_functor,Central> numDiff(functor);
105     numDiff.df(x, jac);
106 
107     VERIFY_IS_APPROX(jac, actual_jac);
108 }
109 
test_NumericalDiff()110 void test_NumericalDiff()
111 {
112     CALL_SUBTEST(test_forward());
113     CALL_SUBTEST(test_central());
114 }
115