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Replace buggy/awkward Combine with principled operator*, remove toFactor

release/4.3a0
Frank Dellaert 2022-01-15 15:12:55 -05:00
parent 0909e98389
commit f9dd225ca5
6 changed files with 204 additions and 89 deletions
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79
gtsam/discrete/DiscreteConditional.cpp
View File

@ -30,6 +30,7 @@
#include <string>
#include <vector>
#include <utility>
#include <set>
using namespace std;
using std::stringstream;
@ -38,37 +39,77 @@ using std::pair;
namespace gtsam {
// Instantiate base class
template class GTSAM_EXPORT Conditional<DecisionTreeFactor, DiscreteConditional> ;
template class GTSAM_EXPORT
Conditional<DecisionTreeFactor, DiscreteConditional>;
/* ******************************************************************************** */
/* ************************************************************************** */
DiscreteConditional::DiscreteConditional(const size_t nrFrontals,
const DecisionTreeFactor& f) :
BaseFactor(f / (*f.sum(nrFrontals))), BaseConditional(nrFrontals) {
}
const DecisionTreeFactor& f)
: BaseFactor(f / (*f.sum(nrFrontals))), BaseConditional(nrFrontals) {}
/* ******************************************************************************** */
DiscreteConditional::DiscreteConditional(const DecisionTreeFactor& joint,
const DecisionTreeFactor& marginal) :
BaseFactor(
ISDEBUG("DiscreteConditional::COUNT") ? joint : joint / marginal), BaseConditional(
joint.size()-marginal.size()) {
if (ISDEBUG("DiscreteConditional::DiscreteConditional"))
cout << (firstFrontalKey()) << endl; //TODO Print all keys
}
/* ************************************************************************** */
DiscreteConditional::DiscreteConditional(size_t nrFrontals,
const DiscreteKeys& keys,
const ADT& potentials)
: BaseFactor(keys, potentials), BaseConditional(nrFrontals) {}
/* ******************************************************************************** */
/* ************************************************************************** */
DiscreteConditional::DiscreteConditional(const DecisionTreeFactor& joint,
const DecisionTreeFactor& marginal, const Ordering& orderedKeys) :
DiscreteConditional(joint, marginal) {
const DecisionTreeFactor& marginal)
: BaseFactor(joint / marginal),
BaseConditional(joint.size() - marginal.size()) {}
/* ************************************************************************** */
DiscreteConditional::DiscreteConditional(const DecisionTreeFactor& joint,
const DecisionTreeFactor& marginal,
const Ordering& orderedKeys)
: DiscreteConditional(joint, marginal) {
keys_.clear();
keys_.insert(keys_.end(), orderedKeys.begin(), orderedKeys.end());
}
/* ******************************************************************************** */
/* ************************************************************************** */
DiscreteConditional::DiscreteConditional(const Signature& signature)
: BaseFactor(signature.discreteKeys(), signature.cpt()),
BaseConditional(1) {}
/* ************************************************************************** */
DiscreteConditional DiscreteConditional::operator*(
const DiscreteConditional& other) const {
// Take union of frontal keys
std::set<Key> newFrontals;
for (auto&& key : this->frontals()) newFrontals.insert(key);
for (auto&& key : other.frontals()) newFrontals.insert(key);
// Check if frontals overlapped
if (nrFrontals() + other.nrFrontals() > newFrontals.size())
throw std::invalid_argument(
"DiscreteConditional::operator* called with overlapping frontal keys.");
// Now, add cardinalities.
DiscreteKeys discreteKeys;
for (auto&& key : frontals())
discreteKeys.emplace_back(key, cardinality(key));
for (auto&& key : other.frontals())
discreteKeys.emplace_back(key, other.cardinality(key));
// Sort
std::sort(discreteKeys.begin(), discreteKeys.end());
// Add parents to set, to make them unique
std::set<DiscreteKey> parents;
for (auto&& key : this->parents())
if (!newFrontals.count(key)) parents.emplace(key, cardinality(key));
for (auto&& key : other.parents())
if (!newFrontals.count(key)) parents.emplace(key, other.cardinality(key));
// Finally, add parents to keys, in order
for (auto&& dk : parents) discreteKeys.push_back(dk);
ADT product = ADT::apply(other, ADT::Ring::mul);
return DiscreteConditional(newFrontals.size(), discreteKeys, product);
}
/* ******************************************************************************** */
void DiscreteConditional::print(const string& s,
const KeyFormatter& formatter) const {
@ -82,7 +123,7 @@ void DiscreteConditional::print(const string& s,
cout << formatter(*it) << " ";
}
}
cout << ")";
cout << "):\n";
ADT::print("");
cout << endl;
}

74
gtsam/discrete/DiscreteConditional.h
View File

@ -49,14 +49,21 @@ class GTSAM_EXPORT DiscreteConditional
/// @name Standard Constructors
/// @{
/** default constructor needed for serialization */
/// Default constructor needed for serialization.
DiscreteConditional() {}
/** constructor from factor */
/// Construct from factor, taking the first `nFrontals` keys as frontals.
DiscreteConditional(size_t nFrontals, const DecisionTreeFactor& f);
/**
* Construct from DiscreteKeys and AlgebraicDecisionTree, taking the first
* `nFrontals` keys as frontals, in the order given.
*/
DiscreteConditional(size_t nFrontals, const DiscreteKeys& keys,
const ADT& potentials);
/** Construct from signature */
DiscreteConditional(const Signature& signature);
explicit DiscreteConditional(const Signature& signature);
/**
* Construct from key, parents, and a Signature::Table specifying the
@ -86,27 +93,38 @@ class GTSAM_EXPORT DiscreteConditional
DiscreteConditional(const DiscreteKey& key, const std::string& spec)
: DiscreteConditional(Signature(key, {}, spec)) {}
/** construct P(X|Y)=P(X,Y)/P(Y) from P(X,Y) and P(Y) */
/**
* @brief construct P(X|Y) = f(X,Y)/f(Y) from f(X,Y) and f(Y)
* Assumes but *does not check* that f(Y)=sum_X f(X,Y).
*/
DiscreteConditional(const DecisionTreeFactor& joint,
const DecisionTreeFactor& marginal);
/** construct P(X|Y)=P(X,Y)/P(Y) from P(X,Y) and P(Y) */
/**
* @brief construct P(X|Y) = f(X,Y)/f(Y) from f(X,Y) and f(Y)
* Assumes but *does not check* that f(Y)=sum_X f(X,Y).
* Makes sure the keys are ordered as given. Does not check orderedKeys.
*/
DiscreteConditional(const DecisionTreeFactor& joint,
const DecisionTreeFactor& marginal,
const Ordering& orderedKeys);
/**
* Combine several conditional into a single one.
* The conditionals must be given in increasing order, meaning that the
* parents of any conditional may not include a conditional coming before it.
* @param firstConditional Iterator to the first conditional to combine, must
* dereference to a shared_ptr<DiscreteConditional>.
* @param lastConditional Iterator to after the last conditional to combine,
* must dereference to a shared_ptr<DiscreteConditional>.
* */
template <typename ITERATOR>
static shared_ptr Combine(ITERATOR firstConditional,
ITERATOR lastConditional);
* @brief Combine two conditionals, yielding a new conditional with the union
* of the frontal keys, ordered by gtsam::Key.
*
* The two conditionals must make a valid Bayes net fragment, i.e.,
* the frontal variables cannot overlap, and must be acyclic:
* Example of correct use:
* P(A,B) = P(A|B) * P(B)
* P(A,B|C) = P(A|B) * P(B|C)
* P(A,B,C) = P(A,B|C) * P(C)
* Example of incorrect use:
* P(A|B) * P(A|C) = ?
* P(A|B) * P(B|A) = ?
* We check for overlapping frontals, but do *not* check for cyclic.
*/
DiscreteConditional operator*(const DiscreteConditional& other) const;
/// @}
/// @name Testable
@ -136,11 +154,6 @@ class GTSAM_EXPORT DiscreteConditional
return ADT::operator()(values);
}
/** Convert to a factor */
DecisionTreeFactor::shared_ptr toFactor() const {
return DecisionTreeFactor::shared_ptr(new DecisionTreeFactor(*this));
}
/** Restrict to given parent values, returns DecisionTreeFactor */
DecisionTreeFactor::shared_ptr choose(
const DiscreteValues& parentsValues) const;
@ -208,23 +221,4 @@ class GTSAM_EXPORT DiscreteConditional
template <>
struct traits<DiscreteConditional> : public Testable<DiscreteConditional> {};
/* ************************************************************************* */
template <typename ITERATOR>
DiscreteConditional::shared_ptr DiscreteConditional::Combine(
ITERATOR firstConditional, ITERATOR lastConditional) {
// TODO: check for being a clique
// multiply all the potentials of the given conditionals
size_t nrFrontals = 0;
DecisionTreeFactor product;
for (ITERATOR it = firstConditional; it != lastConditional;
++it, ++nrFrontals) {
DiscreteConditional::shared_ptr c = *it;
DecisionTreeFactor::shared_ptr factor = c->toFactor();
product = (*factor) * product;
}
// and then create a new multi-frontal conditional
return boost::make_shared<DiscreteConditional>(nrFrontals, product);
}
} // namespace gtsam

1
gtsam/discrete/discrete.i
View File

@ -102,7 +102,6 @@ virtual class DiscreteConditional : gtsam::DecisionTreeFactor {
void printSignature(
string s = "Discrete Conditional: ",
const gtsam::KeyFormatter& formatter = gtsam::DefaultKeyFormatter) const;
gtsam::DecisionTreeFactor* toFactor() const;
gtsam::DecisionTreeFactor* choose(
const gtsam::DiscreteValues& parentsValues) const;
gtsam::DecisionTreeFactor* likelihood(

2
gtsam/discrete/tests/testDecisionTreeFactor.cpp
View File

@ -60,7 +60,7 @@ TEST(DecisionTreeFactor, multiplication) {
DiscretePrior prior(v1 % "1/3");
DecisionTreeFactor f1(v0 & v1, "1 2 3 4");
DecisionTreeFactor expected(v0 & v1, "0.25 1.5 0.75 3");
CHECK(assert_equal(expected, prior * f1));
CHECK(assert_equal(expected, static_cast<DecisionTreeFactor>(prior) * f1));
CHECK(assert_equal(expected, f1 * prior));
// Multiply two factors

124
gtsam/discrete/tests/testDiscreteConditional.cpp
View File

@ -34,20 +34,21 @@ using namespace gtsam;
TEST(DiscreteConditional, constructors) {
DiscreteKey X(0, 2), Y(2, 3), Z(1, 2); // watch ordering !
DiscreteConditional expected(X | Y = "1/1 2/3 1/4");
EXPECT_LONGS_EQUAL(0, *(expected.beginFrontals()));
EXPECT_LONGS_EQUAL(2, *(expected.beginParents()));
EXPECT(expected.endParents() == expected.end());
EXPECT(expected.endFrontals() == expected.beginParents());
DiscreteConditional actual(X | Y = "1/1 2/3 1/4");
EXPECT_LONGS_EQUAL(0, *(actual.beginFrontals()));
EXPECT_LONGS_EQUAL(2, *(actual.beginParents()));
EXPECT(actual.endParents() == actual.end());
EXPECT(actual.endFrontals() == actual.beginParents());
DecisionTreeFactor f1(X & Y, "0.5 0.4 0.2 0.5 0.6 0.8");
DiscreteConditional actual1(1, f1);
EXPECT(assert_equal(expected, actual1, 1e-9));
DiscreteConditional expected1(1, f1);
EXPECT(assert_equal(expected1, actual, 1e-9));
DecisionTreeFactor f2(
X & Y & Z, "0.2 0.5 0.3 0.6 0.4 0.7 0.25 0.55 0.35 0.65 0.45 0.75");
DiscreteConditional actual2(1, f2);
EXPECT(assert_equal(f2 / *f2.sum(1), *actual2.toFactor(), 1e-9));
DecisionTreeFactor expected2 = f2 / *f2.sum(1);
EXPECT(assert_equal(expected2, static_cast<DecisionTreeFactor>(actual2)));
}
/* ************************************************************************* */
@ -61,6 +62,7 @@ TEST(DiscreteConditional, constructors_alt_interface) {
r3 += 1.0, 4.0;
table += r1, r2, r3;
DiscreteConditional actual1(X, {Y}, table);
DecisionTreeFactor f1(X & Y, "0.5 0.4 0.2 0.5 0.6 0.8");
DiscreteConditional expected1(1, f1);
EXPECT(assert_equal(expected1, actual1, 1e-9));
@ -68,43 +70,109 @@ TEST(DiscreteConditional, constructors_alt_interface) {
DecisionTreeFactor f2(
X & Y & Z, "0.2 0.5 0.3 0.6 0.4 0.7 0.25 0.55 0.35 0.65 0.45 0.75");
DiscreteConditional actual2(1, f2);
EXPECT(assert_equal(f2 / *f2.sum(1), *actual2.toFactor(), 1e-9));
DecisionTreeFactor expected2 = f2 / *f2.sum(1);
EXPECT(assert_equal(expected2, static_cast<DecisionTreeFactor>(actual2)));
}
/* ************************************************************************* */
TEST(DiscreteConditional, constructors2) {
// Declare keys and ordering
DiscreteKey C(0, 2), B(1, 2);
DecisionTreeFactor actual(C & B, "0.8 0.75 0.2 0.25");
Signature signature((C | B) = "4/1 3/1");
DiscreteConditional expected(signature);
DecisionTreeFactor::shared_ptr expectedFactor = expected.toFactor();
EXPECT(assert_equal(*expectedFactor, actual));
DiscreteConditional actual(signature);
DecisionTreeFactor expected(C & B, "0.8 0.75 0.2 0.25");
EXPECT(assert_equal(expected, static_cast<DecisionTreeFactor>(actual)));
}
/* ************************************************************************* */
TEST(DiscreteConditional, constructors3) {
// Declare keys and ordering
DiscreteKey C(0, 2), B(1, 2), A(2, 2);
DecisionTreeFactor actual(C & B & A, "0.8 0.5 0.5 0.2 0.2 0.5 0.5 0.8");
Signature signature((C | B, A) = "4/1 1/1 1/1 1/4");
DiscreteConditional expected(signature);
DecisionTreeFactor::shared_ptr expectedFactor = expected.toFactor();
EXPECT(assert_equal(*expectedFactor, actual));
DiscreteConditional actual(signature);
DecisionTreeFactor expected(C & B & A, "0.8 0.5 0.5 0.2 0.2 0.5 0.5 0.8");
EXPECT(assert_equal(expected, static_cast<DecisionTreeFactor>(actual)));
}
/* ************************************************************************* */
TEST(DiscreteConditional, Combine) {
// Check calculation of joint P(A,B)
TEST(DiscreteConditional, Multiply) {
DiscreteKey A(0, 2), B(1, 2);
vector<DiscreteConditional::shared_ptr> c;
c.push_back(boost::make_shared<DiscreteConditional>(A | B = "1/2 2/1"));
c.push_back(boost::make_shared<DiscreteConditional>(B % "1/2"));
DecisionTreeFactor factor(A & B, "0.111111 0.444444 0.222222 0.222222");
DiscreteConditional expected(2, factor);
auto actual = DiscreteConditional::Combine(c.begin(), c.end());
EXPECT(assert_equal(expected, *actual, 1e-5));
}
DiscreteConditional conditional(A | B = "1/2 2/1");
DiscreteConditional prior(B % "1/2");
// P(A,B) = P(A|B) * P(B) = P(B) * P(A|B)
for (auto&& actual : {prior * conditional, conditional * prior}) {
EXPECT_LONGS_EQUAL(2, actual.nrFrontals());
KeyVector frontals(actual.beginFrontals(), actual.endFrontals());
EXPECT((frontals == KeyVector{0, 1}));
for (auto&& it : actual.enumerate()) {
const DiscreteValues& v = it.first;
EXPECT_DOUBLES_EQUAL(actual(v), conditional(v) * prior(v), 1e-9);
}
}
}
/* ************************************************************************* */
// Check calculation of conditional joint P(A,B|C)
TEST(DiscreteConditional, Multiply2) {
DiscreteKey A(0, 2), B(1, 2), C(2, 2);
DiscreteConditional A_given_B(A | B = "1/3 3/1");
DiscreteConditional B_given_C(B | C = "1/3 3/1");
// P(A,B|C) = P(A|B)P(B|C) = P(B|C)P(A|B)
for (auto&& actual : {A_given_B * B_given_C, B_given_C * A_given_B}) {
EXPECT_LONGS_EQUAL(2, actual.nrFrontals());
EXPECT_LONGS_EQUAL(1, actual.nrParents());
KeyVector frontals(actual.beginFrontals(), actual.endFrontals());
EXPECT((frontals == KeyVector{0, 1}));
for (auto&& it : actual.enumerate()) {
const DiscreteValues& v = it.first;
EXPECT_DOUBLES_EQUAL(actual(v), A_given_B(v) * B_given_C(v), 1e-9);
}
}
}
/* ************************************************************************* */
// Check calculation of conditional joint P(A,B|C), double check keys
TEST(DiscreteConditional, Multiply3) {
DiscreteKey A(1, 2), B(2, 2), C(0, 2); // different keys!!!
DiscreteConditional A_given_B(A | B = "1/3 3/1");
DiscreteConditional B_given_C(B | C = "1/3 3/1");
// P(A,B|C) = P(A|B)P(B|C) = P(B|C)P(A|B)
for (auto&& actual : {A_given_B * B_given_C, B_given_C * A_given_B}) {
EXPECT_LONGS_EQUAL(2, actual.nrFrontals());
EXPECT_LONGS_EQUAL(1, actual.nrParents());
KeyVector frontals(actual.beginFrontals(), actual.endFrontals());
EXPECT((frontals == KeyVector{1, 2}));
for (auto&& it : actual.enumerate()) {
const DiscreteValues& v = it.first;
EXPECT_DOUBLES_EQUAL(actual(v), A_given_B(v) * B_given_C(v), 1e-9);
}
}
}
/* ************************************************************************* */
// Check calculation of conditional joint P(A,B,C|D,E) = P(A,B|D) P(C|D,E)
TEST(DiscreteConditional, Multiply4) {
DiscreteKey A(0, 2), B(1, 2), C(2, 2), D(4, 2), E(3, 2);
DiscreteConditional A_given_B(A | B = "1/3 3/1");
DiscreteConditional B_given_D(B | D = "1/3 3/1");
DiscreteConditional AB_given_D = A_given_B * B_given_D;
DiscreteConditional C_given_DE((C | D, E) = "4/1 1/1 1/1 1/4");
// P(A,B,C|D,E) = P(A,B|D) P(C|D,E) = P(C|D,E) P(A,B|D)
for (auto&& actual : {AB_given_D * C_given_DE, C_given_DE * AB_given_D}) {
EXPECT_LONGS_EQUAL(3, actual.nrFrontals());
EXPECT_LONGS_EQUAL(2, actual.nrParents());
KeyVector frontals(actual.beginFrontals(), actual.endFrontals());
EXPECT((frontals == KeyVector{0, 1, 2}));
KeyVector parents(actual.beginParents(), actual.endParents());
EXPECT((parents == KeyVector{3, 4}));
for (auto&& it : actual.enumerate()) {
const DiscreteValues& v = it.first;
EXPECT_DOUBLES_EQUAL(actual(v), AB_given_D(v) * C_given_DE(v), 1e-9);
}
}
}
/* ************************************************************************* */
TEST(DiscreteConditional, likelihood) {
DiscreteKey X(0, 2), Y(1, 3);

13
gtsam/discrete/tests/testDiscretePrior.cpp
View File

@ -42,6 +42,19 @@ TEST(DiscretePrior, constructors) {
EXPECT(assert_equal(expected, actual2, 1e-9));
}
/* ************************************************************************* */
TEST(DiscretePrior, Multiply) {
DiscreteKey A(0, 2), B(1, 2);
DiscreteConditional conditional(A | B = "1/2 2/1");
DiscretePrior prior(B, "1/2");
DiscreteConditional actual = prior * conditional; // P(A|B) * P(B)
EXPECT_LONGS_EQUAL(2, actual.nrFrontals()); // = P(A,B)
DecisionTreeFactor factor(A & B, "1 4 2 2");
DiscreteConditional expected(2, factor);
EXPECT(assert_equal(expected, actual, 1e-5));
}
/* ************************************************************************* */
TEST(DiscretePrior, operator) {
DiscretePrior prior(X % "2/3");