gtsam/gtsam/base/tests/testGroup.cpp

144 lines
4.3 KiB
C++

/* ----------------------------------------------------------------------------
* GTSAM Copyright 2010, Georgia Tech Research Corporation,
* Atlanta, Georgia 30332-0415
* All Rights Reserved
* Authors: Frank Dellaert, et al. (see THANKS for the full author list)
* See LICENSE for the license information
* -------------------------------------------------------------------------- */
/**
* @file testGroup.cpp
* @brief Unit tests for groups
* @author Frank Dellaert
**/
#include <gtsam/base/Group.h>
#include <gtsam/base/Testable.h>
#include <Eigen/Core>
#include <iostream>
namespace gtsam {
/// Symmetric group
template<int N>
class Symmetric: private Eigen::PermutationMatrix<N> {
Symmetric(const Eigen::PermutationMatrix<N>& P) :
Eigen::PermutationMatrix<N>(P) {
}
public:
static Symmetric identity() { return Symmetric(); }
Symmetric() {
Eigen::PermutationMatrix<N>::setIdentity();
}
static Symmetric Transposition(int i, int j) {
Symmetric g;
return g.applyTranspositionOnTheRight(i, j);
}
Symmetric operator*(const Symmetric& other) const {
return Eigen::PermutationMatrix<N>::operator*(other);
}
bool operator==(const Symmetric& other) const {
for (size_t i = 0; i < N; i++)
if (this->indices()[i] != other.indices()[i])
return false;
return true;
}
Symmetric inverse() const {
return Eigen::PermutationMatrix<N>(Eigen::PermutationMatrix<N>::inverse());
}
friend std::ostream &operator<<(std::ostream &os, const Symmetric& m) {
for (size_t i = 0; i < N; i++)
os << m.indices()[i] << " ";
return os;
}
void print(const std::string& s = "") const {
std::cout << s << *this << std::endl;
}
bool equals(const Symmetric<N>& other, double tol = 0) const {
return this->indices() == other.indices();
}
};
/// Define permutation group traits to be a model of the Multiplicative Group concept
template<int N>
struct traits<Symmetric<N> > : internal::MultiplicativeGroupTraits<Symmetric<N> >,
Testable<Symmetric<N> > {
};
} // namespace gtsam
#include <gtsam/base/Testable.h>
#include <CppUnitLite/TestHarness.h>
using namespace std;
using namespace gtsam;
//******************************************************************************
typedef Symmetric<2> S2;
TEST(Group, S2) {
S2 e, s1 = S2::Transposition(0, 1);
BOOST_CONCEPT_ASSERT((IsGroup<S2>));
EXPECT(check_group_invariants(e, s1));
}
//******************************************************************************
typedef Symmetric<3> S3;
TEST(Group, S3) {
S3 e, s1 = S3::Transposition(0, 1), s2 = S3::Transposition(1, 2);
BOOST_CONCEPT_ASSERT((IsGroup<S3>));
EXPECT(check_group_invariants(e, s1));
EXPECT(assert_equal(s1, s1 * e));
EXPECT(assert_equal(s1, e * s1));
EXPECT(assert_equal(e, s1 * s1));
S3 g = s1 * s2; // 1 2 0
EXPECT(assert_equal(s1, g * s2));
EXPECT(assert_equal(e, compose_pow(g, 0)));
EXPECT(assert_equal(g, compose_pow(g, 1)));
EXPECT(assert_equal(e, compose_pow(g, 3))); // g is generator of Z3 subgroup
}
//******************************************************************************
// The direct product of S2=Z2 and S3 is the symmetry group of a hexagon,
// i.e., the dihedral group of order 12 (denoted Dih6 because 6-sided polygon)
namespace gtsam {
typedef DirectProduct<S2, S3> Dih6;
std::ostream &operator<<(std::ostream &os, const Dih6& m) {
os << "( " << m.first << ", " << m.second << ")";
return os;
}
// Provide traits with Testable
template<>
struct traits<Dih6> : internal::MultiplicativeGroupTraits<Dih6> {
static void Print(const Dih6& m, const string& s = "") {
cout << s << m << endl;
}
static bool Equals(const Dih6& m1, const Dih6& m2, double tol = 1e-8) {
return m1 == m2;
}
};
} // namespace gtsam
TEST(Group, Dih6) {
Dih6 e, g(S2::Transposition(0, 1),
S3::Transposition(0, 1) * S3::Transposition(1, 2));
BOOST_CONCEPT_ASSERT((IsGroup<Dih6>));
EXPECT(check_group_invariants(e, g));
EXPECT(assert_equal(e, compose_pow(g, 0)));
EXPECT(assert_equal(g, compose_pow(g, 1)));
EXPECT(assert_equal(e, compose_pow(g, 6))); // g is generator of Z6 subgroup
}
//******************************************************************************
int main() {
TestResult tr;
return TestRegistry::runAllTests(tr);
}
//******************************************************************************