gtsam/gtsam_unstable/nonlinear/Expression-inl.h

459 lines
11 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 Expression-inl.h
* @date September 18, 2014
* @author Frank Dellaert
* @author Paul Furgale
* @brief Internals for Expression.h, not for general consumption
*/
#pragma once
#include <gtsam/nonlinear/Values.h>
#include <gtsam/base/Matrix.h>
#include <boost/foreach.hpp>
namespace gtsam {
template<typename T>
class Expression;
typedef std::map<Key, Matrix> JacobianMap;
//-----------------------------------------------------------------------------
/**
* Value and Jacobians
*/
template<class T>
class Augmented {
private:
T value_;
JacobianMap jacobians_;
typedef std::pair<Key, Matrix> Pair;
/// Insert terms into jacobians_, premultiplying by H, adding if already exists
void add(const Matrix& H, const JacobianMap& terms) {
BOOST_FOREACH(const Pair& term, terms) {
JacobianMap::iterator it = jacobians_.find(term.first);
if (it != jacobians_.end())
it->second += H * term.second;
else
jacobians_[term.first] = H * term.second;
}
}
public:
/// Construct value that does not depend on anything
Augmented(const T& t) :
value_(t) {
}
/// Construct value dependent on a single key
Augmented(const T& t, Key key) :
value_(t) {
size_t n = t.dim();
jacobians_[key] = Eigen::MatrixXd::Identity(n, n);
}
/// Construct value, pre-multiply jacobians by H
Augmented(const T& t, const Matrix& H, const JacobianMap& jacobians) :
value_(t) {
add(H, jacobians);
}
/// Construct value, pre-multiply jacobians by H
Augmented(const T& t, const Matrix& H1, const JacobianMap& jacobians1,
const Matrix& H2, const JacobianMap& jacobians2) :
value_(t) {
add(H1, jacobians1);
add(H2, jacobians2);
}
/// Return value
const T& value() const {
return value_;
}
/// Return jacobians
const JacobianMap& jacobians() const {
return jacobians_;
}
/// Not dependent on any key
bool constant() const {
return jacobians_.empty();
}
/// debugging
void print(const KeyFormatter& keyFormatter = DefaultKeyFormatter) {
BOOST_FOREACH(const Pair& term, jacobians_)
std::cout << "(" << keyFormatter(term.first) << ", " << term.second.rows()
<< "x" << term.second.cols() << ") ";
std::cout << std::endl;
}
};
//-----------------------------------------------------------------------------
/**
* Expression node. The superclass for objects that do the heavy lifting
* An Expression<T> has a pointer to an ExpressionNode<T> underneath
* allowing Expressions to have polymorphic behaviour even though they
* are passed by value. This is the same way boost::function works.
* http://loki-lib.sourceforge.net/html/a00652.html
*/
template<class T>
class ExpressionNode {
protected:
ExpressionNode() {
}
public:
/// Destructor
virtual ~ExpressionNode() {
}
/// Return keys that play in this expression as a set
virtual std::set<Key> keys() const = 0;
/// Return value
virtual T value(const Values& values) const = 0;
/// Return value and derivatives
virtual Augmented<T> augmented(const Values& values) const = 0;
};
//-----------------------------------------------------------------------------
/// Constant Expression
template<class T>
class ConstantExpression: public ExpressionNode<T> {
/// The constant value
T constant_;
/// Constructor with a value, yielding a constant
ConstantExpression(const T& value) :
constant_(value) {
}
friend class Expression<T> ;
public:
/// Destructor
virtual ~ConstantExpression() {
}
/// Return keys that play in this expression, i.e., the empty set
virtual std::set<Key> keys() const {
std::set<Key> keys;
return keys;
}
/// Return value
virtual T value(const Values& values) const {
return constant_;
}
/// Return value and derivatives
virtual Augmented<T> augmented(const Values& values) const {
T t = value(values);
return Augmented<T>(t);
}
};
//-----------------------------------------------------------------------------
/// Leaf Expression
template<class T>
class LeafExpression: public ExpressionNode<T> {
/// The key into values
Key key_;
/// Constructor with a single key
LeafExpression(Key key) :
key_(key) {
}
friend class Expression<T> ;
public:
/// Destructor
virtual ~LeafExpression() {
}
/// Return keys that play in this expression
virtual std::set<Key> keys() const {
std::set<Key> keys;
keys.insert(key_);
return keys;
}
/// Return value
virtual T value(const Values& values) const {
return values.at<T>(key_);
}
/// Return value and derivatives
virtual Augmented<T> augmented(const Values& values) const {
T t = value(values);
return Augmented<T>(t, key_);
}
};
//-----------------------------------------------------------------------------
/// Unary Expression
template<class T, class A>
class UnaryExpression: public ExpressionNode<T> {
protected:
boost::shared_ptr<ExpressionNode<A> > expressionA_;
/// Constructor with one input argument expression
UnaryExpression(const Expression<A>& e) :
expressionA_(e.root()) {
}
public:
/// Destructor
virtual ~UnaryExpression() {
}
/// Return keys that play in this expression
virtual std::set<Key> keys() const {
return expressionA_->keys();
}
};
//-----------------------------------------------------------------------------
/// Nullary Method Expression
template<class T, class A>
class NullaryMethodExpression: public UnaryExpression<T, A> {
public:
typedef T (A::*method)(boost::optional<Matrix&>) const;
private:
method method_;
/// Constructor with a unary function f, and input argument e
NullaryMethodExpression(const Expression<A>& e, method f) :
UnaryExpression<T, A>(e), method_(f) {
}
friend class Expression<T> ;
public:
/// Destructor
virtual ~NullaryMethodExpression() {
}
/// Return value
virtual T value(const Values& values) const {
using boost::none;
return (this->expressionA_->value(values).*(method_))(none);
}
/// Return value and derivatives
virtual Augmented<T> augmented(const Values& values) const {
using boost::none;
Augmented<A> argument = this->expressionA_->augmented(values);
Matrix H;
T t = (argument.value().*(method_))(
argument.constant() ? none : boost::optional<Matrix&>(H));
return Augmented<T>(t, H, argument.jacobians());
}
};
//-----------------------------------------------------------------------------
/// Unary Function Expression
template<class T, class A>
class UnaryFunctionExpression: public UnaryExpression<T, A> {
public:
typedef boost::function<T(const A&, boost::optional<Matrix&>)> function;
private:
function function_;
/// Constructor with a unary function f, and input argument e
UnaryFunctionExpression(function f, const Expression<A>& e) :
UnaryExpression<T, A>(e), function_(f) {
}
friend class Expression<T> ;
public:
/// Destructor
virtual ~UnaryFunctionExpression() {
}
/// Return value
virtual T value(const Values& values) const {
return function_(this->expressionA_->value(values), boost::none);
}
/// Return value and derivatives
virtual Augmented<T> augmented(const Values& values) const {
using boost::none;
Augmented<A> argument = this->expressionA_->augmented(values);
Matrix H;
T t = function_(argument.value(),
argument.constant() ? none : boost::optional<Matrix&>(H));
return Augmented<T>(t, H, argument.jacobians());
}
};
//-----------------------------------------------------------------------------
/// Binary function Expression
template<class T, class A1, class A2>
class BinaryExpression: public ExpressionNode<T> {
public:
typedef boost::function<
T(const A1&, const A2&, boost::optional<Matrix&>,
boost::optional<Matrix&>)> function;
private:
boost::shared_ptr<ExpressionNode<A1> > expressionA1_;
boost::shared_ptr<ExpressionNode<A2> > expressionA2_;
function function_;
/// Constructor with a binary function f, and two input arguments
BinaryExpression(function f, //
const Expression<A1>& e1, const Expression<A2>& e2) :
expressionA1_(e1.root()), expressionA2_(e2.root()), function_(f) {
}
friend class Expression<T> ;
public:
/// Destructor
virtual ~BinaryExpression() {
}
/// Return keys that play in this expression
virtual std::set<Key> keys() const {
std::set<Key> keys1 = expressionA1_->keys();
std::set<Key> keys2 = expressionA2_->keys();
keys1.insert(keys2.begin(), keys2.end());
return keys1;
}
/// Return value
virtual T value(const Values& values) const {
using boost::none;
return function_(expressionA1_->value(values), expressionA2_->value(values),
none, none);
}
/// Return value and derivatives
virtual Augmented<T> augmented(const Values& values) const {
using boost::none;
Augmented<A1> argument1 = expressionA1_->augmented(values);
Augmented<A2> argument2 = expressionA2_->augmented(values);
Matrix H1, H2;
T t = function_(argument1.value(), argument2.value(),
argument1.constant() ? none : boost::optional<Matrix&>(H1),
argument2.constant() ? none : boost::optional<Matrix&>(H2));
return Augmented<T>(t, H1, argument1.jacobians(), H2, argument2.jacobians());
}
};
//-----------------------------------------------------------------------------
/// Binary Expression
template<class T, class A1, class A2>
class MethodExpression: public ExpressionNode<T> {
public:
typedef T (A1::*method)(const A2&, boost::optional<Matrix&>,
boost::optional<Matrix&>) const;
private:
boost::shared_ptr<ExpressionNode<A1> > expressionA1_;
boost::shared_ptr<ExpressionNode<A2> > expressionA2_;
method method_;
/// Constructor with a binary function f, and two input arguments
MethodExpression(const Expression<A1>& e1, method f, const Expression<A2>& e2) :
expressionA1_(e1.root()), expressionA2_(e2.root()), method_(f) {
}
friend class Expression<T> ;
public:
/// Destructor
virtual ~MethodExpression() {
}
/// Return keys that play in this expression
virtual std::set<Key> keys() const {
std::set<Key> keys1 = expressionA1_->keys();
std::set<Key> keys2 = expressionA2_->keys();
keys1.insert(keys2.begin(), keys2.end());
return keys1;
}
/// Return value
virtual T value(const Values& values) const {
using boost::none;
return (expressionA1_->value(values).*(method_))(expressionA2_->value(values),
none, none);
}
/// Return value and derivatives
virtual Augmented<T> augmented(const Values& values) const {
using boost::none;
Augmented<A1> argument1 = expressionA1_->augmented(values);
Augmented<A2> argument2 = expressionA2_->augmented(values);
Matrix H1, H2;
T t = (argument1.value().*(method_))(argument2.value(),
argument1.constant() ? none : boost::optional<Matrix&>(H1),
argument2.constant() ? none : boost::optional<Matrix&>(H2));
return Augmented<T>(t, H1, argument1.jacobians(), H2, argument2.jacobians());
}
};
}