jaccardIndexOf function

double jaccardIndexOf(String source, String target, { int ngram = 1, bool ignoreCase = false, bool ignoreWhitespace = false, bool ignoreNumbers = false, bool alphaNumericOnly = false, })

Returns the Jaccard index between two strings.

Parameters

• source is the variant string
• target is the prototype string
• if ignoreCase is true, the character case shall be ignored.
• if ignoreWhitespace is true, space, tab, newlines etc whitespace characters will be ignored.
• if ignoreNumbers is true, numbers will be ignored.
• if alphaNumericOnly is true, only letters and digits will be matched.
• ngram is the size a single item group. If n = 1, each individual items are considered separately. If n = 2, two consecutive items are grouped together and treated as one.

TIPS: You can pass both ignoreNumbers and alphaNumericOnly to true to ignore everything else except letters.

Details

Jaccard index is a metric used to measure similarity between two samples sets. This is known by several other names:

• Jaccard similarity coefficient
• Tanimoto index
• Tanimoto coefficient

Tversky index is a generalization of Jaccard index when alpha = 1, and beta = 1

See Also: tverskyIndex, jaccardIndex

---

Complexity: Time O(n log n) | Space O(n)

Implementation

double jaccardIndexOf(
  String source,
  String target, {
  int ngram = 1,
  bool ignoreCase = false,
  bool ignoreWhitespace = false,
  bool ignoreNumbers = false,
  bool alphaNumericOnly = false,
}) {
  return tverskyIndexOf(
    source,
    target,
    alpha: 1,
    beta: 1,
    ngram: ngram,
    ignoreCase: ignoreCase,
    ignoreWhitespace: ignoreWhitespace,
    ignoreNumbers: ignoreNumbers,
    alphaNumericOnly: alphaNumericOnly,
  );
}