StopFilter

Removes stop words from the token stream.

Import

import StopFilter from 'dynamosearch/filters/StopFilter';

Constructor

new StopFilter(options?: { stopWords?: '_english_' | '_none_' | string[] })

Parameters

• stopWords ('_english_' | '_none_' | string[], optional) - Stop words to remove (default: '_english_')

Examples

Built-in English Stop Words

const filter = new StopFilter({ stopWords: '_english_' });
const tokens = filter.apply([
  { token: 'the', startOffset: 0, endOffset: 3, position: 0 },
  { token: 'quick', startOffset: 4, endOffset: 9, position: 1 },
  { token: 'brown', startOffset: 10, endOffset: 15, position: 2 },
  { token: 'fox', startOffset: 16, endOffset: 19, position: 3 },
]);
// [
//   { token: 'quick', startOffset: 4, endOffset: 9, position: 1 },
//   { token: 'brown', startOffset: 10, endOffset: 15, position: 2 },
//   { token: 'fox', startOffset: 16, endOffset: 19, position: 3 }
// ]

Custom Stop Words

const filter = new StopFilter({ stopWords: ['quick', 'brown'] });
const tokens = filter.apply([
  { token: 'the', startOffset: 0, endOffset: 3, position: 0 },
  { token: 'quick', startOffset: 4, endOffset: 9, position: 1 },
  { token: 'brown', startOffset: 10, endOffset: 15, position: 2 },
  { token: 'fox', startOffset: 16, endOffset: 19, position: 3 },
]);
// [
//   { token: 'the', startOffset: 0, endOffset: 3, position: 0 },
//   { token: 'fox', startOffset: 16, endOffset: 19, position: 3 }
// ]

Available Stop Word Lists

• english - Common English stop words (the, a, an, and, or, but, etc.)
• none - Empty list (no filtering)
• Custom array - Your own list of stop words

Best For

• English text search
• Reducing index size
• Improving search relevance
• Filtering common words

See Also

• StopAnalyzer - Uses this filter
• KeepWordFilter - For keeping specific words