112 lines
2.6 KiB
C++
112 lines
2.6 KiB
C++
/* ----------------------------------------------------------------------------
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* GTSAM Copyright 2010, Georgia Tech Research Corporation,
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* Atlanta, Georgia 30332-0415
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* All Rights Reserved
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* Authors: Frank Dellaert, et al. (see THANKS for the full author list)
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* See LICENSE for the license information
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* -------------------------------------------------------------------------- */
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/**
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* @file DiscretePrior.h
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* @date December 2021
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* @author Frank Dellaert
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*/
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#pragma once
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#include <gtsam/discrete/DiscreteConditional.h>
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#include <string>
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namespace gtsam {
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/**
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* A prior probability on a set of discrete variables.
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* Derives from DiscreteConditional
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*/
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class GTSAM_EXPORT DiscretePrior : public DiscreteConditional {
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public:
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using Base = DiscreteConditional;
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/// @name Standard Constructors
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/// @{
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/// Default constructor needed for serialization.
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DiscretePrior() {}
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/// Constructor from factor.
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DiscretePrior(const DecisionTreeFactor& f) : Base(f.size(), f) {}
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/**
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* Construct from a Signature.
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*
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* Example: DiscretePrior P(D % "3/2");
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*/
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DiscretePrior(const Signature& s) : Base(s) {}
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/**
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* Construct from key and a Signature::Table specifying the
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* conditional probability table (CPT).
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*
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* Example: DiscretePrior P(D, table);
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*/
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DiscretePrior(const DiscreteKey& key, const Signature::Table& table)
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: Base(Signature(key, {}, table)) {}
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/**
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* Construct from key and a string specifying the conditional
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* probability table (CPT).
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*
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* Example: DiscretePrior P(D, "9/1 2/8 3/7 1/9");
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*/
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DiscretePrior(const DiscreteKey& key, const std::string& spec)
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: DiscretePrior(Signature(key, {}, spec)) {}
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/// @}
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/// @name Testable
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/// @{
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/// GTSAM-style print
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void print(
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const std::string& s = "Discrete Prior: ",
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const KeyFormatter& formatter = DefaultKeyFormatter) const override;
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/// @}
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/// @name Standard interface
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/// @{
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/// Evaluate given a single value.
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double operator()(size_t value) const;
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/// We also want to keep the Base version, taking DiscreteValues:
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// TODO(dellaert): does not play well with wrapper!
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// using Base::operator();
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/// Return entire probability mass function.
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std::vector<double> pmf() const;
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/**
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* solve a conditional
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* @return MPE value of the child (1 frontal variable).
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*/
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size_t solve() const { return Base::solve({}); }
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/**
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* sample
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* @return sample from conditional
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*/
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size_t sample() const { return Base::sample(DiscreteValues()); }
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/// @}
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};
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// DiscretePrior
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// traits
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template <>
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struct traits<DiscretePrior> : public Testable<DiscretePrior> {};
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} // namespace gtsam
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