Similarity context

edit

Use a Painless script to create a similarity equation for scoring documents in a query.

Variables

weight (float, read-only)
The weight as calculated by a weight script
query.boost (float, read-only)
The boost value if provided by the query. If this is not provided the value is 1.0f.
field.docCount (long, read-only)
The number of documents that have a value for the current field.
field.sumDocFreq (long, read-only)
The sum of all terms that exist for the current field. If this is not available the value is -1.
field.sumTotalTermFreq (long, read-only)
The sum of occurrences in the index for all the terms that exist in the current field. If this is not available the value is -1.
term.docFreq (long, read-only)
The number of documents that contain the current term in the index.
term.totalTermFreq (long, read-only)
The total occurrences of the current term in the index.
doc.length (long, read-only)
The number of tokens the current document has in the current field. This is decoded from the stored norms and may be approximate for long fields
doc.freq (long, read-only)
The number of occurrences of the current term in the current document for the current field.

Note that the query, field, and term variables are also available to the weight context. They are more efficiently used there, as they are constant for all documents.

For queries that contain multiple terms, the script is called once for each term with that term’s calculated weight, and the results are summed. Note that some terms might have a doc.freq value of 0 on a document, for example if a query uses synonyms.

Return

double
The similarity score for the current document.

API

The standard Painless API is available.