DoublesUnionBuilder (datasketches-java 4.2.0 API)

java.lang.Object
- org.apache.datasketches.quantiles.DoublesUnionBuilder

```
public class DoublesUnionBuilder
extends Object
```
For building a new DoublesSketch Union operation.

Author:

Lee Rhodes

Constructor Summary

Constructors
Constructor Description

DoublesUnionBuilder()
Constructor for a new DoublesUnionBuilder.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`DoublesUnion`	`build()`	Returns a new empty Union object with the current configuration of this Builder.
`DoublesUnion`	`build(org.apache.datasketches.memory.WritableMemory dstMem)`	Returns a new empty Union object with the current configuration of this Builder and the specified backing destination Memory store.
`int`	`getMaxK()`	Gets the current configured maxK
`DoublesUnionBuilder`	`setMaxK(int maxK)`	Sets the parameter masK that determines the maximum size of the sketch that results from a union and its accuracy.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - DoublesUnionBuilder
```
public DoublesUnionBuilder()
```
    Constructor for a new DoublesUnionBuilder. The default configuration is
    
    k: 128. This produces a normalized rank error of about 1.7%
    
    Memory: null
- Method Detail
  - setMaxK
```
public DoublesUnionBuilder setMaxK(int maxK)
```
    Sets the parameter masK that determines the maximum size of the sketch that results from a union and its accuracy.
    
    Parameters:
    
    maxK - determines the accuracy and size of the union and is a maximum. The effective k can be smaller due to unions with smaller k sketches. It is recommended that maxK be a power of 2 to enable unioning of sketches with different k.
    
    Returns:
    
    this builder
  - getMaxK
```
public int getMaxK()
```
    Gets the current configured maxK
    
    Returns:
    
    the current configured maxK
  - build
```
public DoublesUnion build()
```
    Returns a new empty Union object with the current configuration of this Builder.
    
    Returns:
    
    a Union object
  - build
```
public DoublesUnion build(org.apache.datasketches.memory.WritableMemory dstMem)
```
    Returns a new empty Union object with the current configuration of this Builder and the specified backing destination Memory store.
    
    Parameters:
    
    dstMem - the destination memory
    
    Returns:
    
    a Union object