StringMetrics (Simmetrics Core 4.1.1 API)

java.lang.Object
- org.simmetrics.metrics.StringMetrics

```
public final class StringMetrics
extends Object
```
Utility class for string similarity metrics.
Consists of well known string similarity metrics and methods to create string similarity metrics from list- or set metrics. All metrics are setup with sensible defaults, to customize metrics use StringMetricBuilder.
The created similarity metrics are immutable and thread-safe provided all their components are also immutable and thread-safe.

Method Summary

All Methods Static Methods Concrete Methods Deprecated Methods
Modifier and Type	Method and Description
`static StringMetric`	`blockDistance()` Returns a block distance similarity metric over tokens in a string.
`static StringMetric`	`cosineSimilarity()` Returns a cosine similarity metric over tokens in a string.
`static StringMetric`	`create(Metric<String> metric)` Deprecated. Use `StringMetricBuilder` in favor of directly constructing a metric.
`static StringMetric`	`create(Metric<String> metric, Simplifier simplifier)` Deprecated. Use `StringMetricBuilder` in favor of directly constructing a metric.
`static StringMetric`	`createForListMetric(Metric<List<String>> metric, Simplifier simplifier, Tokenizer tokenizer)` Deprecated. Use `StringMetricBuilder` in favor of directly constructing a metric.
`static StringMetric`	`createForListMetric(Metric<List<String>> metric, Tokenizer tokenizer)` Deprecated. Use `StringMetricBuilder` in favor of directly constructing a metric.
`static StringMetric`	`createForMultisetMetric(Metric<com.google.common.collect.Multiset<String>> metric, Simplifier simplifier, Tokenizer tokenizer)` Deprecated. Use `StringMetricBuilder` in favor of directly constructing a metric.
`static StringMetric`	`createForMultisetMetric(Metric<com.google.common.collect.Multiset<String>> metric, Tokenizer tokenizer)` Deprecated. Use `StringMetricBuilder` in favor of directly constructing a metric.
`static StringMetric`	`createForSetMetric(Metric<Set<String>> metric, Simplifier simplifier, Tokenizer tokenizer)` Deprecated. Use `StringMetricBuilder` in favor of directly constructing a metric.
`static StringMetric`	`createForSetMetric(Metric<Set<String>> metric, Tokenizer tokenizer)` Deprecated. Use `StringMetricBuilder` in favor of directly constructing a metric.
`static StringMetric`	`damerauLevenshtein()` Returns a Damerau-Levenshtein similarity metric over tokens in a string.
`static StringMetric`	`dice()` Returns a Dice similarity metric over tokens in a string.
`static StringMetric`	`euclideanDistance()` Returns an Euclidean distance similarity metric over tokens in a string.
`static StringMetric`	`generalizedJaccard()` Returns a generalized Jaccard similarity metric over tokens in a string.
`static StringMetric`	`identity()` Returns an identity string similarity metric.
`static StringMetric`	`jaccard()` Returns a Jaccard similarity metric over tokens in a string.
`static StringMetric`	`jaro()` Returns a Jaro string similarity metric.
`static StringMetric`	`jaroWinkler()` Returns a Jaro-Winkler string similarity metric.
`static StringMetric`	`levenshtein()` Returns a Levenshtein string similarity metric.
`static StringMetric`	`longestCommonSubsequence()` Returns a string similarity metric that uses the `LongestCommonSubsequence` metric.
`static StringMetric`	`longestCommonSubstring()` Returns a similarity metric that uses the `LongestCommonSubstring` metric.
`static StringMetric`	`mongeElkan()` Returns a normalized Monge-Elkan metric over tokens in a string.
`static StringMetric`	`needlemanWunch()` Returns a Needleman-Wunch string similarity metric.
`static StringMetric`	`overlapCoefficient()` Returns an overlap coefficient similarity metric over tokens in a string.
`static StringMetric`	`qGramsDistance()` Returns a q-grams distance similarity metric.
`static StringMetric`	`simonWhite()` Returns a Simon White similarity metric.
`static StringMetric`	`smithWaterman()` Returns a Smith-Waterman string similarity metric.
`static StringMetric`	`smithWatermanGotoh()` Returns a Smith-Waterman-Gotoh string similarity metric.
`static StringMetric`	`soundex()` Deprecated. will be removed due to a lack of a good use case

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Method Detail
  - cosineSimilarity
```
public static StringMetric cosineSimilarity()
```
    Returns a cosine similarity metric over tokens in a string. The tokens are created by splitting the string on whitespace.
    
    Returns:
    
    a cosine similarity metric
    
    See Also:
    
    CosineSimilarity
  - blockDistance
```
public static StringMetric blockDistance()
```
    Returns a block distance similarity metric over tokens in a string. The tokens are created by splitting the string on whitespace.
    
    Returns:
    
    a block distance metric
    
    See Also:
    
    BlockDistance
  - damerauLevenshtein
```
public static StringMetric damerauLevenshtein()
```
    Returns a Damerau-Levenshtein similarity metric over tokens in a string. The tokens are created by splitting the string on whitespace.
    
    Returns:
    
    a Damerau-Levenshtein metric
    
    See Also:
    
    DamerauLevenshtein
  - dice
```
public static StringMetric dice()
```
    Returns a Dice similarity metric over tokens in a string. The tokens are created by splitting the string on whitespace.
    
    Returns:
    
    a dice metric
    
    See Also:
    
    Dice
  - euclideanDistance
```
public static StringMetric euclideanDistance()
```
    Returns an Euclidean distance similarity metric over tokens in a string. The tokens are created by splitting the string on whitespace.
    
    Returns:
    
    a Euclidean distance similarity metric
    
    See Also:
    
    EuclideanDistance
  - generalizedJaccard
```
public static StringMetric generalizedJaccard()
```
    Returns a generalized Jaccard similarity metric over tokens in a string. The tokens are created by splitting the string on whitespace.
    
    Returns:
    
    a generalized Jaccard index metric
    
    See Also:
    
    GeneralizedJaccard
  - identity
```
public static StringMetric identity()
```
    Returns an identity string similarity metric. The metric returns 1.0 when the inputs are equals, and 0.0 when they're not.
    
    Returns:
    
    an identity similarity metric
    
    See Also:
    
    Identity
  - jaccard
```
public static StringMetric jaccard()
```
    Returns a Jaccard similarity metric over tokens in a string. The tokens are created by splitting the string on whitespace.
    
    Returns:
    
    a Jaccard similarity metric
    
    See Also:
    
    Jaccard
  - jaro
```
public static StringMetric jaro()
```
    Returns a Jaro string similarity metric.
    
    Returns:
    
    a Jaro string similarity metric
    
    See Also:
    
    Jaro
  - jaroWinkler
```
public static StringMetric jaroWinkler()
```
    Returns a Jaro-Winkler string similarity metric.
    
    Returns:
    
    a Jaro-Winkler string similarity metric
    
    See Also:
    
    JaroWinkler
  - levenshtein
```
public static StringMetric levenshtein()
```
    Returns a Levenshtein string similarity metric.
    
    Returns:
    
    a Levenshtein string similarity metric
    
    See Also:
    
    Levenshtein
  - mongeElkan
```
public static StringMetric mongeElkan()
```
    Returns a normalized Monge-Elkan metric over tokens in a string. The tokens are created by splitting the string on whitespace. The metric applies Smith-Waterman-Gotoh internally.
    
    Returns:
    
    a normalized Monge-Elkan metric
    
    See Also:
    
    MongeElkan
  - needlemanWunch
```
public static StringMetric needlemanWunch()
```
    Returns a Needleman-Wunch string similarity metric.
    
    Returns:
    
    a Needleman-Wunch string similarity metric
    
    See Also:
    
    NeedlemanWunch
  - overlapCoefficient
```
public static StringMetric overlapCoefficient()
```
    Returns an overlap coefficient similarity metric over tokens in a string. The tokens are created by splitting the string on whitespace.
    
    Returns:
    
    an overlap coefficient metric
    
    See Also:
    
    OverlapCoefficient
  - qGramsDistance
```
public static StringMetric qGramsDistance()
```
    Returns a q-grams distance similarity metric. Q-grams distance applies a block distance similarity similarity metric over all tri-grams in a string.
    
    Returns:
    
    a q-grams distance similarity metric
    
    See Also:
    
    BlockDistance
  - simonWhite
```
public static StringMetric simonWhite()
```
    Returns a Simon White similarity metric. Simon White applies the quantitative version Dice similarity over tokens in a string. The tokens are created by splitting the string on whitespace and taking bi-grams of the created tokens.
    Implementation based on the ideas as outlined in How to Strike a Match by Simon White.
    
    Returns:
    
    a Simon White similarity metric
    
    See Also:
    
    SimonWhite
  - smithWaterman
```
public static StringMetric smithWaterman()
```
    Returns a Smith-Waterman string similarity metric.
    
    Returns:
    
    a Smith-Waterman string similarity metric
    
    See Also:
    
    SmithWaterman
  - smithWatermanGotoh
```
public static StringMetric smithWatermanGotoh()
```
    Returns a Smith-Waterman-Gotoh string similarity metric.
    
    Returns:
    
    a Smith-Waterman-Gotoh string similarity metric
    
    See Also:
    
    SmithWatermanGotoh
  - soundex
```
@Deprecated
public static StringMetric soundex()
```
    Deprecated. will be removed due to a lack of a good use case
    
    Returns a soundex similarity metric. The metric applies the Jaro-Winkler similarity metric over soundex strings.
    
    Returns:
    
    a soundex similarity metric
    
    See Also:
    
    Soundex, JaroWinkler
  - longestCommonSubsequence
```
public static StringMetric longestCommonSubsequence()
```
    Returns a string similarity metric that uses the LongestCommonSubsequence metric.
    
    Returns:
    
    a longest common subsequence metric
  - longestCommonSubstring
```
public static StringMetric longestCommonSubstring()
```
    Returns a similarity metric that uses the LongestCommonSubstring metric.
    
    Returns:
    
    a longest common substring metric
  - create
```
@Deprecated
public static StringMetric create(Metric<String> metric)
```
    Deprecated. Use StringMetricBuilder in favor of directly constructing a metric.
    
    Either constructs a new string similarity metric or returns the original metric.
    
    Parameters:
    
    metric - a metric for strings
    
    Returns:
    
    a similarity metric.
  - create
```
@Deprecated
public static StringMetric create(Metric<String> metric,
                                              Simplifier simplifier)
```
    Deprecated. Use StringMetricBuilder in favor of directly constructing a metric.
    
    Constructs a new composite string similarity metric. The simplifier will be applied before the metric compares the strings.
    
    Parameters:
    
    metric - a list metric
    
    simplifier - a simplifier
    
    Returns:
    
    a new composite similarity metric
    
    Throws:
    
    NullPointerException - when either metric or simplifier are null
    
    See Also:
    
    StringMetricBuilder
  - createForListMetric
```
@Deprecated
public static StringMetric createForListMetric(Metric<List<String>> metric,
                                                           Simplifier simplifier,
                                                           Tokenizer tokenizer)
```
    Deprecated. Use StringMetricBuilder in favor of directly constructing a metric.
    
    Creates a new composite string similarity metric.The tokenizer is used to tokenize the simplified strings. The list metric compares the the tokens.
    
    Parameters:
    
    metric - a list metric
    
    simplifier - a simplifier
    
    tokenizer - a tokenizer
    
    Returns:
    
    a new composite list metric
    
    Throws:
    
    NullPointerException - when either metric, simplifier or tokenizer are null
    
    See Also:
    
    StringMetricBuilder
  - createForListMetric
```
@Deprecated
public static StringMetric createForListMetric(Metric<List<String>> metric,
                                                           Tokenizer tokenizer)
```
    Deprecated. Use StringMetricBuilder in favor of directly constructing a metric.
    
    Creates a new composite string similarity metric. The tokenizer is used to tokenize the strings. The list metric compares the the tokens.
    
    Parameters:
    
    metric - a list metric
    
    tokenizer - a tokenizer
    
    Returns:
    
    a new composite similarity metric
    
    Throws:
    
    NullPointerException - when either metric or tokenizer are null
    
    See Also:
    
    StringMetricBuilder
  - createForSetMetric
```
@Deprecated
public static StringMetric createForSetMetric(Metric<Set<String>> metric,
                                                          Simplifier simplifier,
                                                          Tokenizer tokenizer)
```
    Deprecated. Use StringMetricBuilder in favor of directly constructing a metric.
    
    Creates a new composite string similarity metric.The tokenizer is used to tokenize the simplified strings. The set metric compares the the tokens.
    
    Parameters:
    
    metric - a list metric
    
    simplifier - a simplifier
    
    tokenizer - a tokenizer
    
    Returns:
    
    a new composite similarity metric
    
    Throws:
    
    NullPointerException - when either metric, simplifier or tokenizer are null
    
    See Also:
    
    StringMetricBuilder
  - createForSetMetric
```
@Deprecated
public static StringMetric createForSetMetric(Metric<Set<String>> metric,
                                                          Tokenizer tokenizer)
```
    Deprecated. Use StringMetricBuilder in favor of directly constructing a metric.
    
    Creates a new composite string similarity metric. The tokenizer is used to tokenize the strings. The set metric compares the the tokens.
    
    Parameters:
    
    metric - a set metric
    
    tokenizer - a tokenizer
    
    Returns:
    
    a new composite similarity metric
    
    Throws:
    
    NullPointerException - when either metric or tokenizer are null
    
    See Also:
    
    StringMetricBuilder
  - createForMultisetMetric
```
@Deprecated
public static StringMetric createForMultisetMetric(Metric<com.google.common.collect.Multiset<String>> metric,
                                                               Simplifier simplifier,
                                                               Tokenizer tokenizer)
```
    Deprecated. Use StringMetricBuilder in favor of directly constructing a metric.
    
    Creates a new composite string similarity metric.The tokenizer is used to tokenize the simplified strings. The set metric compares the the tokens.
    
    Parameters:
    
    metric - a list metric
    
    simplifier - a simplifier
    
    tokenizer - a tokenizer
    
    Returns:
    
    a new composite similarity metric
    
    Throws:
    
    NullPointerException - when either metric, simplifier or tokenizer are null
    
    See Also:
    
    StringMetricBuilder
  - createForMultisetMetric
```
@Deprecated
public static StringMetric createForMultisetMetric(Metric<com.google.common.collect.Multiset<String>> metric,
                                                               Tokenizer tokenizer)
```
    Deprecated. Use StringMetricBuilder in favor of directly constructing a metric.
    
    Creates a new composite string similarity metric. The tokenizer is used to tokenize the strings. The set metric compares the the tokens.
    
    Parameters:
    
    metric - a set metric
    
    tokenizer - a tokenizer
    
    Returns:
    
    a new composite similarity metric
    
    Throws:
    
    NullPointerException - when either metric or tokenizer are null
    
    See Also:
    
    StringMetricBuilder

Class StringMetrics

Method Summary

Methods inherited from class java.lang.Object

Method Detail

cosineSimilarity

blockDistance

damerauLevenshtein

dice

euclideanDistance

generalizedJaccard

identity

jaccard

jaro

jaroWinkler

levenshtein

mongeElkan

needlemanWunch

overlapCoefficient

qGramsDistance

simonWhite

smithWaterman

smithWatermanGotoh

soundex

longestCommonSubsequence

longestCommonSubstring

create

create

createForListMetric

createForListMetric

createForSetMetric

createForSetMetric

createForMultisetMetric

createForMultisetMetric