# Uses of Class
org.apache.lucene.queries.function.valuesource.DocFreqValueSource

Packages that use DocFreqValueSource
Package
Description
org.apache.lucene.queries.function.valuesource
A variety of functions to use with FunctionQuery.

## Uses of DocFreqValueSource in org.apache.lucene.queries.function.valuesource

Subclasses of DocFreqValueSource in org.apache.lucene.queries.function.valuesource
Modifier and Type
Class
Description
`class`
`IDFValueSource`
Function that returns `#idf(long, long)` for every document.
`class`
`TermFreqValueSource`
Function that returns `PostingsEnum.freq()` for the supplied term in every document.
`class`
`TFValueSource`
Function that returns `TFIDFSimilarity.tf(float)` for every document.