gtsam/cpp/testBinaryBayesNet.cpp

81 lines
2.2 KiB
C++

/**
* @file testBinaryBayesNet.cpp
* @brief Unit tests for BinaryBayesNet
* @author Manohar Paluri
*/
// STL/C++
#include <iostream>
#include <sstream>
#include <map>
#include <CppUnitLite/TestHarness.h>
#include <boost/tuple/tuple.hpp>
#include <boost/foreach.hpp>
#include <boost/assign/std/vector.hpp> // for operator +=
using namespace boost::assign;
#ifdef HAVE_BOOST_SERIALIZATION
#include <boost/archive/text_oarchive.hpp>
#include <boost/archive/text_iarchive.hpp>
#endif //HAVE_BOOST_SERIALIZATION
#define GTSAM_MAGIC_KEY
#include "BinaryConditional.h"
#include "BayesNet-inl.h"
#include "Ordering.h"
#include "SymbolMap.h"
using namespace std;
using namespace gtsam;
/** A Bayes net made from binary conditional probability tables */
typedef BayesNet<BinaryConditional> BinaryBayesNet;
double probability( BinaryBayesNet & bbn, SymbolMap<bool> & config)
{
double result = 1.0;
BinaryBayesNet::const_iterator it = bbn.begin();
while( it != bbn.end() ){
result *= (*it)->probability(config);
it++;
}
return result;
}
/************************************************************************** */
TEST( BinaryBayesNet, constructor )
{
// small Bayes Net x <- y
// p(y) = 0.2
// p(x|y=0) = 0.3
// p(x|y=1) = 0.6
SymbolMap<bool> config;
config["y"] = false;
config["x"] = false;
// unary conditional for y
boost::shared_ptr<BinaryConditional> py(new BinaryConditional("y",0.2));
DOUBLES_EQUAL(0.8,py->probability(config),0.01);
// single parent conditional for x
vector<double> cpt;
cpt += 0.3, 0.6 ; // array index corresponds to binary parent configuration
boost::shared_ptr<BinaryConditional> px_y(new BinaryConditional("x","y",cpt));
DOUBLES_EQUAL(0.7,px_y->probability(config),0.01);
// push back conditionals in topological sort order (parents last)
BinaryBayesNet bbn;
bbn.push_back(py);
bbn.push_back(px_y);
// Test probability of 00,01,10,11
DOUBLES_EQUAL(0.56,probability(bbn,config),0.01); // P(y=0)P(x=0|y=0) = 0.8 * 0.7 = 0.56;
}
/* ************************************************************************* */
int main() { TestResult tr; return TestRegistry::runAllTests(tr);}
/* ************************************************************************* */