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Fixed special case for root

release/4.3a0
Frank Dellaert 2009-11-09 04:45:38 +00:00
parent cc22e82ca6
commit dd1b023ca9
2 changed files with 52 additions and 18 deletions
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13
cpp/BayesTree-inl.h
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@ -144,11 +144,12 @@ namespace gtsam {
// For now, assume neither is the root
// Combine P(F1|S1), P(S1|R), P(F2|S2), P(S2|R), and P(R)
sharedBayesNet p_FSR = this->shortcut<Factor>(R);
p_FSR->push_front(*this);
p_FSR->push_front(*C2->shortcut<Factor>(R));
p_FSR->push_front(*C2);
p_FSR->push_back(*R);
sharedBayesNet bn(new BayesNet<Conditional>);
if (!isRoot()) bn->push_back(*this); // P(F1|S1)
if (!isRoot()) bn->push_back(*(shortcut<Factor>(R))); // P(S1|R)
if (!C2->isRoot()) bn->push_back(*C2); // P(F2|S2)
if (!C2->isRoot()) bn->push_back(*C2->shortcut<Factor>(R)); // P(S2|R)
bn->push_back(*R); // P(R)
// Find the keys of both C1 and C2
Ordering keys12 = keys();
@ -156,7 +157,7 @@ namespace gtsam {
keys12.unique();
// Calculate the marginal
return marginals<Factor>(*p_FSR,keys12);
return marginals<Factor>(*bn,keys12);
}
/* ************************************************************************* */

57
cpp/testBayesTree.cpp
View File

@ -77,6 +77,12 @@ TEST( BayesTree, constructor )
CHECK(assert_equal(bayesTree,bayesTree2));
}
/* ************************************************************************* */
// Some numbers that should be consistent among all smoother tests
double sigmax1 = 0.786153, sigmax2 = 0.687131, sigmax3 = 0.671512, sigmax4 =
0.669534, sigmax5 = sigmax3, sigmax6 = sigmax2, sigmax7 = sigmax1;
/* ************************************************************************* *
Bayes tree for smoother with "natural" ordering:
C1 x6 x7
@ -86,7 +92,7 @@ C4 x3 : x4
C5 x2 : x3
C6 x1 : x2
/* ************************************************************************* */
TEST( BayesTree, smoother )
TEST( BayesTree, linear_smoother_shortcuts )
{
// Create smoother with 7 nodes
LinearFactorGraph smoother = createSmoother(7);
@ -161,9 +167,8 @@ TEST( BayesTree, balanced_smoother_marginals )
GaussianBayesNet::shared_ptr chordalBayesNet = smoother.eliminate(ordering);
VectorConfig expectedSolution;
Vector delta = zero(2);
BOOST_FOREACH(string key, ordering)
expectedSolution.insert(key,delta);
expectedSolution.insert(key,zero(2));
boost::shared_ptr<VectorConfig> actualSolution = chordalBayesNet->optimize();
CHECK(assert_equal(expectedSolution,*actualSolution,1e-4));
@ -172,19 +177,29 @@ TEST( BayesTree, balanced_smoother_marginals )
LONGS_EQUAL(7,bayesTree.size());
// Check marginal on x1
GaussianBayesNet expected1("x1", delta, 0.786153);
BayesNet<ConditionalGaussian> actual1 = bayesTree.marginal<LinearFactor>("x1");
GaussianBayesNet expected1("x1", zero(2), sigmax1);
BayesNet<ConditionalGaussian> actual1 = bayesTree.marginal<LinearFactor>("x1");
CHECK(assert_equal((BayesNet<ConditionalGaussian>)expected1,actual1,1e-4));
// Check marginal on x2
GaussianBayesNet expected2("x2", delta, 0.687131);
BayesNet<ConditionalGaussian> actual2 = bayesTree.marginal<LinearFactor>("x2");
GaussianBayesNet expected2("x2", zero(2), sigmax2);
BayesNet<ConditionalGaussian> actual2 = bayesTree.marginal<LinearFactor>("x2");
CHECK(assert_equal((BayesNet<ConditionalGaussian>)expected2,actual2,1e-4));
// Check marginal on x3
GaussianBayesNet expected3("x3", delta, 0.671512);
BayesNet<ConditionalGaussian> actual3 = bayesTree.marginal<LinearFactor>("x3");
GaussianBayesNet expected3("x3", zero(2), sigmax3);
BayesNet<ConditionalGaussian> actual3 = bayesTree.marginal<LinearFactor>("x3");
CHECK(assert_equal((BayesNet<ConditionalGaussian>)expected3,actual3,1e-4));
// Check marginal on x4
GaussianBayesNet expected4("x4", zero(2), sigmax4);
BayesNet<ConditionalGaussian> actual4 = bayesTree.marginal<LinearFactor>("x4");
CHECK(assert_equal((BayesNet<ConditionalGaussian>)expected4,actual4,1e-4));
// Check marginal on x7 (should be equal to x1)
GaussianBayesNet expected7("x7", zero(2), sigmax7);
BayesNet<ConditionalGaussian> actual7 = bayesTree.marginal<LinearFactor>("x7");
CHECK(assert_equal((BayesNet<ConditionalGaussian>)expected7,actual7,1e-4));
}
/* ************************************************************************* */
@ -231,7 +246,7 @@ TEST( BayesTree, balanced_smoother_clique_marginals )
Gaussian bayesTree(*chordalBayesNet);
// Check the clique marginal P(C3)
GaussianBayesNet expected("x2",zero(2),0.687131);
GaussianBayesNet expected("x2",zero(2),sigmax2);
Vector sigma = repeat(2, 0.707107);
Matrix A12 = (-0.5)*eye(2);
ConditionalGaussian::shared_ptr cg(new ConditionalGaussian("x1", zero(2), eye(2), "x2", A12, sigma));
@ -258,18 +273,36 @@ TEST( BayesTree, balanced_smoother_joint )
Matrix A = (-0.00429185)*eye(2);
// Check the joint density P(x1,x7) factored as P(x1|x7)P(x7)
GaussianBayesNet expected1("x7", zero(2), 0.786153);
GaussianBayesNet expected1("x7", zero(2), sigmax7);
ConditionalGaussian::shared_ptr cg1(new ConditionalGaussian("x1", zero(2), eye(2), "x7", A, sigma));
expected1.push_front(cg1);
BayesNet<ConditionalGaussian> actual1 = bayesTree.joint<LinearFactor>("x1","x7");
CHECK(assert_equal((BayesNet<ConditionalGaussian>)expected1,actual1,1e-4));
// Check the joint density P(x7,x1) factored as P(x7|x1)P(x1)
GaussianBayesNet expected2("x1", zero(2), 0.786153);
GaussianBayesNet expected2("x1", zero(2), sigmax1);
ConditionalGaussian::shared_ptr cg2(new ConditionalGaussian("x7", zero(2), eye(2), "x1", A, sigma));
expected2.push_front(cg2);
BayesNet<ConditionalGaussian> actual2 = bayesTree.joint<LinearFactor>("x7","x1");
CHECK(assert_equal((BayesNet<ConditionalGaussian>)expected2,actual2,1e-4));
// Check the joint density P(x1,x4), i.e. with a root variable
GaussianBayesNet expected3("x4", zero(2), sigmax4);
Vector sigma14 = repeat(2, 0.784465);
Matrix A14 = (-0.0769231)*eye(2);
ConditionalGaussian::shared_ptr cg3(new ConditionalGaussian("x1", zero(2), eye(2), "x4", A14, sigma14));
expected3.push_front(cg3);
BayesNet<ConditionalGaussian> actual3 = bayesTree.joint<LinearFactor>("x1","x4");
CHECK(assert_equal((BayesNet<ConditionalGaussian>)expected3,actual3,1e-4));
// Check the joint density P(x4,x1), i.e. with a root variable, factored the other way
GaussianBayesNet expected4("x1", zero(2), sigmax1);
Vector sigma41 = repeat(2, 0.668096);
Matrix A41 = (-0.055794)*eye(2);
ConditionalGaussian::shared_ptr cg4(new ConditionalGaussian("x4", zero(2), eye(2), "x1", A41, sigma41));
expected4.push_front(cg4);
BayesNet<ConditionalGaussian> actual4 = bayesTree.joint<LinearFactor>("x4","x1");
CHECK(assert_equal((BayesNet<ConditionalGaussian>)expected4,actual4,1e-4));
}
/* ************************************************************************* */