Text 0.4.0 countvectorizeroptions equals

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CountVectorizerOptions.Equals

Value equality, comparing the stop words as a set rather than as a sequence.

public bool Equals(CountVectorizerOptions other)

Parameters — other is the options object to compare against.

Returns — bool, true when every setting matches and the two stop-word sets hold the same words.

Example — the same words in a different order are the same options.

using Lodestar.Text.Vectorization;

var first = new CountVectorizerOptions { StopWords = new HashSet<string> { "the", "and" } };
var second = new CountVectorizerOptions { StopWords = new HashSet<string> { "and", "the" } };

bool same = first.Equals(second);  // => True

Remarks — a record's synthesised equality would compare StopWords by reference, so two options objects carrying identical words would be unequal — the answer nobody wants and the reason this is hand-written. SetEquals is what it uses, so order does not matter and neither does duplication: ["the", "the"] equals ["the"].

That has a consequence worth knowing, and it is stated on GetHashCode: because equal objects must hash alike, the hash cannot use the stop-word count, since two equal sets can differ in it.

Applies to — net10.0, netstandard2.0.

See also — CountVectorizerOptions, CountVectorizerOptions.GetHashCode.