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1 - Similarity, for code that wants a distance rather than a score.

public static double Distance(ReadOnlySpan<char> a, ReadOnlySpan<char> b, double prefixWeight = 0.1, TextElement element = TextElement.Utf16Unit)

Parameters — a and b are the two strings to compare, prefixWeight is what each shared leading character is worth (0.1 by default) and element says what counts as one character — all three exactly as for Similarity, which this subtracts from 1.

Returns — double in [0, 1], larger meaning less alike.

Exceptions — ArgumentOutOfRangeException when prefixWeight is below 0, above 1, or NaN.

Example — a swapped pair of letters, forgiven almost entirely because the prefix agrees.

using Lodestar.Text.Distances;

double d = JaroWinkler.Distance("MARTHA", "MARHTA");   // => 0.0388…

Remarks — the same measure as Similarity, turned round for code that sorts ascending or thresholds with "at most". Nothing else differs.

It inherits Similarity's cap: a prefixWeight above 0.25 cannot push the similarity past 1, so this never drops below zero.

Applies to — net10.0, netstandard2.0.

See also — JaroWinkler.Similarity, Jaro.Distance, the Python equivalence table.