Relationship With Other Edit Distance Metrics
Levenshtein distance is not the only popular notion of edit distance. Variations can be obtained by changing the set of allowable edit operations: for instance,
- length of the longest common subsequence is the metric obtained by allowing only addition and deletion, not substitution;
- the Damerau–Levenshtein distance allows addition, deletion, substitution, and the transposition of two adjacent characters;
- the Hamming distance only allows substitution (and hence, only applies to strings of the same length).
Edit distance in general is usually defined as a parametrizable metric in which a repertoire of edit operations is available, and each operation is assigned a cost (possibly infinite). This is further generalized by DNA sequence alignment algorithms such as the Smith–Waterman algorithm, which make an operation's cost depend on where it is applied.
Read more about this topic: Levenshtein Distance
Famous quotes containing the words relationship, edit and/or distance:
“Every relationship that does not raise us up pulls us down, and vice versa; this is why men usually sink down somewhat when they take wives while women are usually somewhat raised up. Overly spiritual men require marriage every bit as much as they resist it as bitter medicine.”
—Friedrich Nietzsche (18441900)
“To a philosopher all news, as it is called, is gossip, and they who edit it and read it are old women over their tea.”
—Henry David Thoreau (18171862)
“The mystery of the evening-star brilliant in silence and distance between the downward-surging plunge of the sun and the vast, hollow seething of inpouring night. The magnificence of the watchful morning-star, that watches between the night and the day, the gleaming clue to the two opposites.”
—D.H. (David Herbert)