Class HumanMatchEngine
- All Implemented Interfaces:
MatchEngine
- Since:
- 2 Sep 2005
- Author:
- Mark Taylor
-
Constructor Summary
Constructors -
Method Summary
Modifier and TypeMethodDescriptionReturns a supplier for coverage objects.Returns a factory for MatchKit instances corresponding to the current settings of this object.static MatchEngine
Returns a human-friendly version of a supplied MatchEngine.uk.ac.starlink.table.DescribedValue[]
Returns a set of DescribedValue objects whose values can be modified to modify the matching criteria.uk.ac.starlink.table.ValueInfo
Returns a description of the value returned by theMatchKit.matchScore(java.lang.Object[], java.lang.Object[])
method.double
Returns a scale value for the match score.uk.ac.starlink.table.DescribedValue[]
Returns a set of DescribedValue objects whose values can be modified to tune the performance of the match.uk.ac.starlink.table.ValueInfo[]
Returns a set of ValueInfo objects indicating what is required for the elements of each tuple.boolean
Indicates whether this object simply duplicates the underlying MatchEngine.boolean
isLargeAngle
(uk.ac.starlink.table.ValueInfo info) Indicates whether a given value is recognised as representing a large angle (such as a coordinate of some kind).boolean
isSmallAngle
(uk.ac.starlink.table.ValueInfo info) Indicates whether a given value is recognised as representing a small angle (such as an error of some kind).
-
Constructor Details
-
HumanMatchEngine
Constructor.- Parameters:
baseEngine
- the match engine supplying the base behaviour for this one
-
-
Method Details
-
isIdentity
public boolean isIdentity()Indicates whether this object simply duplicates the underlying MatchEngine.- Returns:
- true if this wrapper makes no changes to underlying behaviour, false if it may make changes
-
getMatchParameters
public uk.ac.starlink.table.DescribedValue[] getMatchParameters()Description copied from interface:MatchEngine
Returns a set of DescribedValue objects whose values can be modified to modify the matching criteria. Typically at least one of these will be some sort of tolerance separation which determines how close tuples must be to count as a match. This match engine's behaviour can be modified by callingDescribedValue.setValue(java.lang.Object)
on the returned objects.- Specified by:
getMatchParameters
in interfaceMatchEngine
- Returns:
- array of described values which influence the match
-
getTuningParameters
public uk.ac.starlink.table.DescribedValue[] getTuningParameters()Description copied from interface:MatchEngine
Returns a set of DescribedValue objects whose values can be modified to tune the performance of the match. This match engine's performance can be influenced by callingDescribedValue.setValue(java.lang.Object)
on the returned objects.Changing these values will make no difference to the output of
MatchKit.matchScore(java.lang.Object[], java.lang.Object[])
, but may change the output ofMatchKit.getBins(java.lang.Object[])
. This may change the CPU and memory requirements of the match, but will not change the result. The default value should be something sensible, so that setting the value of these parameters is not in general required.- Specified by:
getTuningParameters
in interfaceMatchEngine
- Returns:
- array of described values which may influence match performance
-
getTupleInfos
public uk.ac.starlink.table.ValueInfo[] getTupleInfos()Description copied from interface:MatchEngine
Returns a set of ValueInfo objects indicating what is required for the elements of each tuple. The length of this array is the number of elements in the tuple. Each element should at least have a defined name and content class. The info'snullable
attribute has a special meaning: if true it means that it makes sense for this element of the tuple to be always blank (for instance assigned to no column).- Specified by:
getTupleInfos
in interfaceMatchEngine
- Returns:
- array of objects describing the requirements on each element of the tuples used for matching
-
createMatchKitFactory
Description copied from interface:MatchEngine
Returns a factory for MatchKit instances corresponding to the current settings of this object.The returned value is immutable, and is not affected by subsequent changes of the settings of this object.
- Specified by:
createMatchKitFactory
in interfaceMatchEngine
- Returns:
- match kit supplier
-
createCoverageFactory
Description copied from interface:MatchEngine
Returns a supplier for coverage objects. Each such coverage can be used to characterise a region of tuple space. When populated with a set of tuples A, any tuple for which the inclusion function defined by itsCoverage.createTestFactory()
method returns false is guaranteed not to match any tuple in A according to this object's match criteria.The returned value is immutable, and is not affected by subsequent changes of the settings of this object.
If no suitable implementation is available, null may be returned.
- Specified by:
createCoverageFactory
in interfaceMatchEngine
- Returns:
- supplier of coverage objects, or null
-
getScoreScale
public double getScoreScale()Description copied from interface:MatchEngine
Returns a scale value for the match score. The intention is that the result ofmatchScore
/MatchEngine.getScoreScale()
is of order unity, and is thus comparable between different match engines.As a general rule, the result should be the maximum value ever returned from the
matchScore
method, corresponding to the least good successful match. For binary MatchEngine implementations (all matches are either score=0 or failures) a value of 1 is recommended. If nothing reliable can be said about the scale, NaN may be returned.- Specified by:
getScoreScale
in interfaceMatchEngine
- Returns:
- scale of successful match scores, a positive finite number or NaN
-
getMatchScoreInfo
public uk.ac.starlink.table.ValueInfo getMatchScoreInfo()Description copied from interface:MatchEngine
Returns a description of the value returned by theMatchKit.matchScore(java.lang.Object[], java.lang.Object[])
method. The content class should be numeric (though need not beDouble
), and the name, description and units should be descriptive of whatever the physical significance of the value is. If the result ofmatchScore
is not interesting (for instance, if it's always either 0 or -1),null
may be returned.- Specified by:
getMatchScoreInfo
in interfaceMatchEngine
- Returns:
- metadata for the match score results
-
isLargeAngle
public boolean isLargeAngle(uk.ac.starlink.table.ValueInfo info) Indicates whether a given value is recognised as representing a large angle (such as a coordinate of some kind).- Parameters:
info
- value metadata- Returns:
- true if info is known to represent a large angle
-
isSmallAngle
public boolean isSmallAngle(uk.ac.starlink.table.ValueInfo info) Indicates whether a given value is recognised as representing a small angle (such as an error of some kind).- Parameters:
info
- value metadata- Returns:
- true if info is known to represent a small angle
-
getHumanMatchEngine
Returns a human-friendly version of a supplied MatchEngine. If no changes are required, the original instance is returned.- Parameters:
base
- original match engine- Returns:
- human-friendly version
-