lengthSimilarity method

double lengthSimilarity(String other)

Returns the similarity in length between two terms, defined as: lengthSimilarity = 1 minus the log of the ratio between the term lengths, with a floor at 0.0: 1-(log(this.length/other.length))

Returns:

• 1.0 if this and other are the same length; and
• 0.0 if the ratio between term lengths is more than 10 or less than 0.1.

The String and other are converted to lower-case and trimmed for the comparison.

Implementation

double lengthSimilarity(String other) {
  final term = trim().toLowerCase();
  other = other.trim().toLowerCase();
  final logRatio = term.isEmpty
      ? other.isEmpty
          ? 0
          : 1
      : other.isEmpty
          ? 1
          : (log(other.length / term.length)).abs();
  final similarity = logRatio > 1 ? 0.0 : 1.0 - logRatio;
  if (similarity > 1.0) {
    return 1.0;
  }
  return similarity;
}