org.apache.lucene.queries.function.valuesource

## Class DualFloatFunction

- java.lang.Object
- - org.apache.lucene.queries.function.ValueSource
  - - org.apache.lucene.queries.function.valuesource.DualFloatFunction

- Direct Known Subclasses:
    DivFloatFunction, PowFloatFunction

      public abstract class DualFloatFunction
      extends ValueSource

  Abstract `ValueSource` implementation which wraps two ValueSources and applies an extendible float function to their values.

- - ### Field Summary

    Fields
    Modifier and Type | Field and Description
    --- | ---
    `protected ValueSource` | `a`
    `protected ValueSource` | `b`

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `DualFloatFunction(ValueSource a, ValueSource b)`

  - ### Method Summary

    All Methods Instance Methods Abstract Methods Concrete Methods
    Modifier and Type | Method and Description
    --- | ---
    `void` | `createWeight(Map context, IndexSearcher searcher)` Implementations should propagate createWeight to sub-ValueSources which can optionally store weight info in the context.
    `String` | `description()` description of field, used in explain()
    `boolean` | `equals(Object o)`
    `protected abstract float` | `func(int doc, FunctionValues aVals, FunctionValues bVals)`
    `FunctionValues` | `getValues(Map context, LeafReaderContext readerContext)` Gets the values for this reader and the context that was previously passed to createWeight().
    `int` | `hashCode()`
    `protected abstract String` | `name()`

    - ### Methods inherited from class org.apache.lucene.queries.function.ValueSource

      `asDoubleValuesSource, asLongValuesSource, fromDoubleValuesSource, getSortField, newContext, toString`

    - ### Methods inherited from class java.lang.Object

      `clone, finalize, getClass, notify, notifyAll, wait, wait, wait`

- - ### Field Detail

    - #### a

          protected final ValueSource a

    - #### b

          protected final ValueSource b

  - ### Constructor Detail

    - #### DualFloatFunction

          public DualFloatFunction(ValueSource a,
                                   ValueSource b)

      Parameters:
        `a` - the base.
        `b` - the exponent.

  - ### Method Detail

    - #### name

          protected abstract String name()

    - #### func

          protected abstract float func(int doc,
                                        FunctionValues aVals,
                                        FunctionValues bVals)
                                 throws IOException

      Throws:
        `IOException`

    - #### description

          public String description()

      Description copied from class: `ValueSource`
      description of field, used in explain()
      Specified by:
        `description` in class `ValueSource`

    - #### getValues

          public FunctionValues getValues(Map context,
                                          LeafReaderContext readerContext)
                                   throws IOException

      Description copied from class: `ValueSource`
      Gets the values for this reader and the context that was previously passed to createWeight(). The values must be consumed in a forward docID manner, and you must call this method again to iterate through the values again.
      Specified by:
        `getValues` in class `ValueSource`
      Throws:
        `IOException`

    - #### createWeight

          public void createWeight(Map context,
                                   IndexSearcher searcher)
                            throws IOException

      Description copied from class: `ValueSource`
      Implementations should propagate createWeight to sub-ValueSources which can optionally store weight info in the context. The context object will be passed to getValues() where this info can be retrieved.
      Overrides:
        `createWeight` in class `ValueSource`
      Throws:
        `IOException`

    - #### hashCode

          public int hashCode()

      Specified by:
        `hashCode` in class `ValueSource`

    - #### equals

          public boolean equals(Object o)

      Specified by:
        `equals` in class `ValueSource`

Copyright © 2000-2019 Apache Software Foundation. All Rights Reserved.