StringMetrics (SimMetrics 3.2.3 API)

java.lang.Object
- org.simmetrics.StringMetrics

```
public final class StringMetrics
extends Object
```
Utility class for StringMetrics.
Consists of well known metrics and methods to create string metrics from list- or set metrics. All metrics are setup with sensible defaults, to customize metrics use StringMetricBuilder.
The available metrics are:
- Block Distance
- Cosine Similarity
- Damerau Levenshtein
- Dice Similarity
- Euclidean Distance
- Jaccard Similarity
- Jaro
- Jaro-Winkler
- LevenShtein
- Matching Coefficient
- Monge-Elkan
- NeedleMan Wunch
- Overlap Coefficient
- q-Grams Distance
- SimonWhite
- Smith-Waterman
- Smith-Waterman-Gotoh
- Soundex
All methods return immutable objects provided the arguments are also immutable.

Method Summary

All Methods Static Methods Concrete Methods Deprecated Methods
Modifier and Type	Method and Description
`static StringMetric`	`blockDistance()` Returns a string metric that uses a `Tokenizers.whitespace()` and the `BlockDistance` metric.
`static float[]`	`compare(StringMetric metric, String c, List<String> strings)` Deprecated. trivial with no clear use case
`static float[]`	`compare(StringMetric metric, String c, String... strings)` Deprecated. trivial with no clear use case
`static float[]`	`compareArrays(StringMetric metric, String[] a, String[] b)` Deprecated. trivial with no clear use case
`static StringMetric`	`cosineSimilarity()` Returns a string metric that uses a `Tokenizers.whitespace()` and the `CosineSimilarity` metric.
`static StringMetric`	`create(Metric<String> metric)` Either constructs a new string metric or returns the original metric.
`static StringMetric`	`create(Metric<String> metric, Simplifier simplifier)` Constructs a new composite string metric.
`static StringMetric`	`createForListMetric(Metric<List<String>> metric, Simplifier simplifier, Tokenizer tokenizer)` Creates a new composite string metric.The tokenizer is used to tokenize the simplified strings.
`static StringMetric`	`createForListMetric(Metric<List<String>> metric, Tokenizer tokenizer)` Creates a new composite string metric.
`static StringMetric`	`createForSetMetric(Metric<Set<String>> metric, Simplifier simplifier, Tokenizer tokenizer)` Creates a new composite string metric.The tokenizer is used to tokenize the simplified strings.
`static StringMetric`	`createForSetMetric(Metric<Set<String>> metric, Tokenizer tokenizer)` Creates a new composite string metric.
`static StringMetric`	`damerauLevenshtein()` Returns a string metric that uses a `DamerauLevenshtein` metric.
`static StringMetric`	`diceSimilarity()` Returns a string metric that uses a `Tokenizers.whitespace()` and the `DiceSimilarity` metric.
`static StringMetric`	`euclideanDistance()` Returns a string metric that uses a `Tokenizers.whitespace()` and the `EuclideanDistance` metric.
`static StringMetric`	`identity()` Returns an string metric that uses the `Identity` metric.
`static StringMetric`	`jaccardSimilarity()` Returns a string metric that uses a `Tokenizers.whitespace()` and the `JaccardSimilarity` metric.
`static StringMetric`	`jaro()` Returns a string metric that uses the `Jaro` metric.
`static StringMetric`	`jaroWinkler()` Returns a string metric that uses the `JaroWinkler` metric.
`static StringMetric`	`levenshtein()` Returns a string metric that uses the `Levenshtein` metric.
`static StringMetric`	`matchingCoefficient()` Returns a string metric that uses a `Tokenizers.whitespace()` and the `MatchingCoefficient` metric.
`static StringMetric`	`mongeElkan()` Returns a string metric that uses a `Tokenizers.whitespace()` and the `MongeElkan` metric with an internal `SmithWatermanGotoh` metric.
`static StringMetric`	`needlemanWunch()` Returns a string metric that uses the `NeedlemanWunch` metric.
`static StringMetric`	`overlapCoefficient()` Returns a string metric that uses a `Tokenizers.whitespace()` and the `OverlapCoefficient` metric.
`static StringMetric`	`qGramsDistance()` Returns a string metric that uses a `Tokenizers.qGramWithPadding(int)` for `q=3` and the `BlockDistance` metric.
`static StringMetric`	`simonWhite()` Returns a string metric that uses a `Tokenizers.whitespace()` followed by a `Tokenizers.qGramWithPadding(int)` for `q=2` and the `SimonWhite` metric.
`static StringMetric`	`smithWaterman()` Returns a string metric that uses the `SmithWaterman` metric.
`static StringMetric`	`smithWatermanGotoh()` Returns a string metric that uses the `SmithWatermanGotoh` metric.
`static StringMetric`	`soundex()` Returns a string metric that uses a `Soundex` and `JaroWinkler` metric.

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

- Method Detail
  - compare
```
@Deprecated
public static float[] compare(StringMetric metric,
                                          String c,
                                          List<String> strings)
```
    Deprecated. trivial with no clear use case
    
    Applies a metric to a string c and a list of strings. Returns an array with the similarity value for c and each string in the list.
    
    Parameters:
    
    metric - to compare c with each each value in the list
    
    c - string to compare the list against
    
    strings - to compare c against
    
    Returns:
    
    an array with the similarity value for c and each string in the list
  - compare
```
@Deprecated
public static float[] compare(StringMetric metric,
                                          String c,
                                          String... strings)
```
    Deprecated. trivial with no clear use case
    
    Applies a metric to a string c and a list of strings. Returns an array with the similarity value for c and each string in the list.
    
    Parameters:
    
    metric - to compare c with each each value in the list
    
    c - string to compare the list against
    
    strings - to compare c against
    
    Returns:
    
    an array with the similarity value for c and each string in the list
  - compareArrays
```
@Deprecated
public static float[] compareArrays(StringMetric metric,
                                                String[] a,
                                                String[] b)
```
    Deprecated. trivial with no clear use case
    
    Applies a metric to each pair of a[n] and b[n]. Returns an array where result[n] contains the similarity between a[n] and b[n].
    
    Parameters:
    
    metric - to compare each element in a and b
    
    a - array of string to compare
    
    b - array of string to compare
    
    Returns:
    
    a list of similarity values for each pair a[n] b[n]
    
    Throws:
    
    IllegalArgumentException - when a and b are of a different length
  - cosineSimilarity
```
public static StringMetric cosineSimilarity()
```
    Returns a string metric that uses a Tokenizers.whitespace() and the CosineSimilarity metric.
    
    Returns:
    
    a cosine similarity metric
  - create
```
public static StringMetric create(Metric<String> metric)
```
    Either constructs a new string metric or returns the original metric.
    
    Parameters:
    
    metric - a metric for strings
    
    Returns:
    
    a string metric.
  - create
```
public static StringMetric create(Metric<String> metric,
                                  Simplifier simplifier)
```
    Constructs a new composite string metric. The simplifier will be applied before the metric compares the strings.
    
    Parameters:
    
    metric - a list metric
    
    simplifier - a simplifier
    
    Returns:
    
    a new composite string metric
    
    Throws:
    
    NullPointerException - when either metric or simplifier are null
    
    See Also:
    
    StringMetricBuilder
  - createForListMetric
```
public static StringMetric createForListMetric(Metric<List<String>> metric,
                                               Simplifier simplifier,
                                               Tokenizer tokenizer)
```
    Creates a new composite string 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
```
public static StringMetric createForListMetric(Metric<List<String>> metric,
                                               Tokenizer tokenizer)
```
    Creates a new composite string 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 string metric
    
    Throws:
    
    NullPointerException - when either metric or tokenizer are null
    
    See Also:
    
    StringMetricBuilder
  - createForSetMetric
```
public static StringMetric createForSetMetric(Metric<Set<String>> metric,
                                              Simplifier simplifier,
                                              Tokenizer tokenizer)
```
    Creates a new composite string 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 string metric
    
    Throws:
    
    NullPointerException - when either metric, simplifier or tokenizer are null
    
    See Also:
    
    StringMetricBuilder
  - createForSetMetric
```
public static StringMetric createForSetMetric(Metric<Set<String>> metric,
                                              Tokenizer tokenizer)
```
    Creates a new composite string 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 string metric
    
    Throws:
    
    NullPointerException - when either metric or tokenizer are null
    
    See Also:
    
    StringMetricBuilder
  - blockDistance
```
public static StringMetric blockDistance()
```
    Returns a string metric that uses a Tokenizers.whitespace() and the BlockDistance metric.
    
    Returns:
    
    a block distance metric
  - damerauLevenshtein
```
public static StringMetric damerauLevenshtein()
```
    Returns a string metric that uses a DamerauLevenshtein metric.
    
    Returns:
    
    a dice similarity metric
  - diceSimilarity
```
public static StringMetric diceSimilarity()
```
    Returns a string metric that uses a Tokenizers.whitespace() and the DiceSimilarity metric.
    
    Returns:
    
    a dice similarity metric
  - euclideanDistance
```
public static StringMetric euclideanDistance()
```
    Returns a string metric that uses a Tokenizers.whitespace() and the EuclideanDistance metric.
    
    Returns:
    
    a Euclidean distance similarity metric
  - identity
```
public static StringMetric identity()
```
    Returns an string metric that uses the Identity metric.
    
    Returns:
    
    an identity string metric
  - jaccardSimilarity
```
public static StringMetric jaccardSimilarity()
```
    Returns a string metric that uses a Tokenizers.whitespace() and the JaccardSimilarity metric.
    
    Returns:
    
    a Jaccard similarity metric
  - jaro
```
public static StringMetric jaro()
```
    Returns a string metric that uses the Jaro metric.
    
    Returns:
    
    a Jaro metric
  - jaroWinkler
```
public static StringMetric jaroWinkler()
```
    Returns a string metric that uses the JaroWinkler metric.
    
    Returns:
    
    a Jaro-Winkler metric
  - levenshtein
```
public static StringMetric levenshtein()
```
    Returns a string metric that uses the Levenshtein metric.
    
    Returns:
    
    a Levenshtein metric
  - matchingCoefficient
```
public static StringMetric matchingCoefficient()
```
    Returns a string metric that uses a Tokenizers.whitespace() and the MatchingCoefficient metric.
    
    Returns:
    
    a matching coefficient metric
  - mongeElkan
```
public static StringMetric mongeElkan()
```
    Returns a string metric that uses a Tokenizers.whitespace() and the MongeElkan metric with an internal SmithWatermanGotoh metric.
    
    Returns:
    
    a Monge-Elkan metric
  - needlemanWunch
```
public static StringMetric needlemanWunch()
```
    Returns a string metric that uses the NeedlemanWunch metric.
    
    Returns:
    
    a Needleman-Wunch metric
  - overlapCoefficient
```
public static StringMetric overlapCoefficient()
```
    Returns a string metric that uses a Tokenizers.whitespace() and the OverlapCoefficient metric.
    
    Returns:
    
    a overlap coefficient metric
  - qGramsDistance
```
public static StringMetric qGramsDistance()
```
    Returns a string metric that uses a Tokenizers.qGramWithPadding(int) for q=3 and the BlockDistance metric.
    
    Returns:
    
    a q-grams distance metric
  - simonWhite
```
public static StringMetric simonWhite()
```
    Returns a string metric that uses a Tokenizers.whitespace() followed by a Tokenizers.qGramWithPadding(int) for q=2 and the SimonWhite metric.
    
    Returns:
    
    a Simon White metric
  - smithWaterman
```
public static StringMetric smithWaterman()
```
    Returns a string metric that uses the SmithWaterman metric.
    
    Returns:
    
    a Smith-Waterman metric
  - smithWatermanGotoh
```
public static StringMetric smithWatermanGotoh()
```
    Returns a string metric that uses the SmithWatermanGotoh metric.
    
    Returns:
    
    a Smith-Waterman-Gotoh metric
  - soundex
```
public static StringMetric soundex()
```
    Returns a string metric that uses a Soundex and JaroWinkler metric.
    
    Returns:
    
    a Soundex metric

Class StringMetrics

Method Summary

Methods inherited from class java.lang.Object

Method Detail

compare

compare

compareArrays

cosineSimilarity

create

create

createForListMetric

createForListMetric

createForSetMetric

createForSetMetric

blockDistance

damerauLevenshtein

diceSimilarity

euclideanDistance

identity

jaccardSimilarity

jaro

jaroWinkler

levenshtein

matchingCoefficient

mongeElkan

needlemanWunch

overlapCoefficient

qGramsDistance

simonWhite

smithWaterman

smithWatermanGotoh

soundex