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// Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
#pragma once
#include <vespa/searchlib/common/feature.h>
#include <vector>
#include <cstdint>
namespace search::features::fieldmatch {
/**
* The parameters to a string match metric calculator.
*
* @author <a href="mailto:bratseth@yahoo-inc.com">Jon Bratseth</a>
* @author Simon Thoresen Hult
* @version $Id$
*/
class Params {
public:
/**
* Creates a marcg metrics object initialized to the default values.
*/
Params();
/**
* Returns whether or not this parameter object contains valid content. If it is NOT valid, a descriptive string
* will be logged for reference.
*
* @return Whether or not this object is valid.
*/
bool valid();
/**
* Sets the number of tokens within which proximity matters. Default: 10
*
* @param proximityLimit The number of tokens.
* @param This, to allow chaining.
*/
Params &setProximityLimit(uint32_t proximityLimit) {
_proximityLimit = proximityLimit;
return *this;
}
/**
* Returns the number of tokens within which proximity matters. Default: 10
*
* @return The number of tokens.
*/
uint32_t getProximityLimit() const {
return _proximityLimit;
}
/**
* Sets the proximity table deciding the importance of separations of various distances, The table must have size
* proximityLimit*2+1, where the first half is for reverse direction distances. The table must only contain values
* between 0 and 1, where 1 is "perfect" and 0 is "worst".
*
* @param proximityTable The proximity table.
* @return This, to allow chaining.
*/
Params &setProximityTable(const std::vector<feature_t> &proximityTable) {
_proximityTable = proximityTable;
return *this;
}
/**
* Returns the current proxmity table. The default table is calculated by <code>1/2^(n/2)</code> on the right order
* side, and <code>1/2^(n/2) /3</code> on the reverse order side where n is the distance between the tokens.
*
* @return The proximity table.
*/
const std::vector<feature_t> &getProximityTable() const {
return _proximityTable;
}
/**
* Returns the maximal number of <i>alternative</i> segmentations allowed in addition to the first one found.
* Default is 10000. This will prefer to not consider iterations on segments that are far out in the field, and
* which starts late in the query.
*
* @return The max number of alternative iterations.
*/
uint32_t getMaxAlternativeSegmentations() const {
return _maxAlternativeSegmentations;
}
/**
* Sets the maximal number of alternative segmentations allowed in addition to the first one found.
*
* @param maxAlternativeSegmentations The max number of alternative iterations.
* @return This, to allow chaining.
*/
Params &setMaxAlternativeSegmentations(uint32_t maxAlternativeSegmentations) {
_maxAlternativeSegmentations = maxAlternativeSegmentations;
return *this;
}
/**
* Returns the number of occurrences each word is normalized against. This should be set as the number above which
* additional occurrences of the term has no real significance. The default is 100.
*
* @return The max number of occurences.
*/
uint32_t getMaxOccurrences() const {
return _maxOccurrences;
}
/**
* Sets the number occurences each word is normalized against.
*
* @params maxOccurences The max number of occurences.
* @return This, to allow chaining.
*/
Params &setMaxOccurrences(uint32_t maxOccurrences) {
_maxOccurrences = maxOccurrences;
return *this;
}
/**
* Returns a number between 0 and 1 which determines the importance of field completeness in relation to query
* completeness in the <code>match</code> and <code>completeness</code> metrics. Default is 0.05
*
* @return The importance of field completeness.
*/
feature_t getFieldCompletenessImportance() const {
return _fieldCompletenessImportance;
}
/**
* Sets the importance of this field's completeness.
*
* @param fieldCompletenessImportance The importance of field completeness.
* @return This, to allow chaining.
*/
Params &setFieldCompletenessImportance(feature_t fieldCompletenessImportance) {
_fieldCompletenessImportance = fieldCompletenessImportance;
return *this;
}
/**
* Returns the importance of the match having high proximity and being complete, relative to
* segmentProximityImportance, occurrenceImportance and earlinessImportance in the <code>match</code>
* metric. Default: 0.9
*
* @return The importance of proximity AND completeness.
*/
feature_t getProximityCompletenessImportance() const {
return _proximityCompletenessImportance;
}
/**
* Sets the importance of this fiel's proximity AND completeness.
*
* @param proximityCompletenessImportance The importance of proximity AND completeness.
* @return This, to allow chaining.
*/
Params &setProximityCompletenessImportance(feature_t proximityCompletenessImportance) {
_proximityCompletenessImportance = proximityCompletenessImportance;
return *this;
}
/**
* Returns the importance of the match occuring early in the query, relative to segmentProximityImportance,
* occurrenceImportance and proximityCompletenessImportance in the <code>match</code> metric. Default: 0.05
*
* @return The importance of earliness.
*/
feature_t getEarlinessImportance() const {
return _earlinessImportance;
}
/**
* Sets the importance of the match occuring early in the query.
*
* @param earlinessImportance The importance of earliness.
* @return This, to allow chaining.
*/
Params &setEarlinessImportance(feature_t earlinessImportance) {
_earlinessImportance = earlinessImportance;
return *this;
}
/**
* Returns the importance of multiple segments being close to each other, relative to earlinessImportance,
* occurrenceImportance and proximityCompletenessImportance in the <code>match</code> metric. Default: 0.05
*
* @return The importance of segment proximity.
*/
feature_t getSegmentProximityImportance() const {
return _segmentProximityImportance;
}
/**
* Sets the importance of multiple segments being close to each other.
*
* @param segmentProximityImportance The importance of segment proximity.
* @return This, to allow chaining.
*/
Params &setSegmentProximityImportance(feature_t segmentProximityImportance) {
_segmentProximityImportance = segmentProximityImportance;
return *this;
}
/**
* Returns the importance of having many occurrences of the query terms, relative to earlinessImportance,
* segmentProximityImportance and proximityCompletenessImportance in the <code>match</code> metric. Default: 0.05
*
* @return The importance of many occurences.
*/
feature_t getOccurrenceImportance() const {
return _occurrenceImportance;
}
/**
* Sets the importance of having many occurences of the query terms.
*
* @param occurenceImportance The importance of many occurences.
* @return This, to allow chaining.
*/
Params &setOccurrenceImportance(feature_t occurrenceImportance) {
_occurrenceImportance = occurrenceImportance;
return *this;
}
/**
* Returns the normalized importance of relatedness used in the <code>match</code> metric. Default: 0.9
*
* @return The importance of relatedness.
*/
feature_t getRelatednessImportance() const {
return _relatednessImportance;
}
/**
* Sets the normalized importance of relatedness used in the <code>match</code> metric.
*
* @param relatednessImportance The importance of relatedness.
* @return This, to allow chaining.
*/
Params &setRelatednessImportance(feature_t relatednessImportance) {
_relatednessImportance = relatednessImportance;
return *this;
}
private:
uint32_t _proximityLimit;
uint32_t _maxAlternativeSegmentations;
uint32_t _maxOccurrences;
feature_t _proximityCompletenessImportance;
feature_t _relatednessImportance;
feature_t _earlinessImportance;
feature_t _segmentProximityImportance;
feature_t _occurrenceImportance;
feature_t _fieldCompletenessImportance;
std::vector<feature_t> _proximityTable;
};
}
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