/// \file
-/// \brief Defines classes Evidence and Observation
-/// \todo Describe tabular data file format
-/// \todo Improve documentation
+/// \brief Defines class Evidence, which stores multiple observations of joint states of variables
#ifndef __defined_libdai_evidence_h
namespace dai {
-/// Stores observed values of a subset of variables
-class Observation {
- private:
- /// Used to store the state of some variables
- std::map<Var, size_t> _obs;
-
- public:
- /// Default constructor
- Observation() : _obs() {}
-
- /// Get all observations
- const std::map<Var, size_t>& observations() const { return _obs; }
-
- /// Add an observation
- void addObservation( Var node, size_t setting );
-
- /// Clamp variables in the graphical model to their observed values
- void applyEvidence( InfAlg& alg ) const;
-};
-
-
-/// Stores multiple joint observations of sets of variables.
-/** The Evidence class stores multiple samples, where each sample is the joint
- * observation of the states of some variables.
+/// Stores a data set consisting of multiple samples, where each sample is the observed joint state of some variables.
+/** \note Each sample can describe the joint state of a different set of variables,
+ * in order to be able to deal with missing data.
+ *
+ * \author Charles Vaske
*/
class Evidence {
+ public:
+ /// Stores joint state of a set of variables
+ typedef std::map<Var, size_t> Observation;
+
private:
- /// Each sample is the joint observation of the states of some variables
+ /// Each sample is an observed joint state of some variables
std::vector<Observation> _samples;
public:
/// Default constructor
Evidence() : _samples() {}
- /// Construct from existing samples
+ /// Construct from \a samples
Evidence( std::vector<Observation> &samples ) : _samples(samples) {}
- /// Read in tabular data from a stream.
- /** Each line contains one sample, and the first line is a header line with names.
- */
- void addEvidenceTabFile( std::istream& is, std::map<std::string, Var> &varMap );
-
- /// Read in tabular data from a stream.
- /** Each line contains one sample, and the first line is a header line with
- * variable labels which should correspond with a subset of the variables in fg.
+ /// Read in tabular data from a stream and add the read samples to \c *this.
+ /** \param is Input stream in .tab file format, describing joint observations of variables in \a fg
+ * \param fg Factor graph describing the corresponding variables
+ * \see \ref fileformats-evidence
+ * \throw INVALID_EVIDENCE_FILE if the input stream is not valid
*/
void addEvidenceTabFile( std::istream& is, FactorGraph& fg );
/// \name Iterator interface
//@{
- /// Iterator over the elements
+ /// Iterator over the samples
typedef std::vector<Observation>::iterator iterator;
- /// Constant iterator over the elements
+ /// Constant iterator over the samples
typedef std::vector<Observation>::const_iterator const_iterator;
- /// Returns iterator that points to the first element
+ /// Returns iterator that points to the first sample
iterator begin() { return _samples.begin(); }
- /// Returns constant iterator that points to the first element
+ /// Returns constant iterator that points to the first sample
const_iterator begin() const { return _samples.begin(); }
- /// Returns iterator that points beyond the last element
+ /// Returns iterator that points beyond the last sample
iterator end() { return _samples.end(); }
- /// Returns constant iterator that points beyond the last element
+ /// Returns constant iterator that points beyond the last sample
const_iterator end() const { return _samples.end(); }
//@}
+
+ private:
+ /// Read in tabular data from a stream and add the read samples to \c *this.
+ void addEvidenceTabFile( std::istream& is, std::map<std::string, Var> &varMap );
};