Combinations.LexicographicComparator (VirtualDataSet API)

java.lang.Object
- org.apache.commons.numbers.combinatorics.Combinations.LexicographicComparator

All Implemented Interfaces:

java.io.Serializable, java.util.Comparator<int[]>

Enclosing class:

Combinations
```
public static class Combinations.LexicographicComparator
extends java.lang.Object
implements java.util.Comparator<int[]>, java.io.Serializable
```
Defines a lexicographic ordering of the combinations. The comparison is based on the value (in base 10) represented by the digit (interpreted in base n) in the input array, in reverse order. For example if c is {3, 2, 1}, and n is 3, the method will return 18.

See Also:

Serialized Form

Constructor Summary

Constructors
Constructor Description

LexicographicComparator(int n, int k)

Method Summary

Modifier and Type	Method	Description
`int`	`compare(int[] c1, int[] c2)`
`int`	`getK()`	Gets the number of elements in each combination.
`int`	`getN()`	Gets the size of the set from which combinations are drawn.

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

Methods inherited from interface java.util.Comparator
equals, reversed, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

- Constructor Detail
  - LexicographicComparator
```
public LexicographicComparator(int n,
                               int k)
```
    Parameters:
    
    n - Size of the set from which subsets are selected.
    
    k - Size of the subsets to be enumerated.
- Method Detail
  - getN
```
public int getN()
```
    Gets the size of the set from which combinations are drawn.
    
    Returns:
    
    the size of the universe.
  - getK
```
public int getK()
```
    Gets the number of elements in each combination.
    
    Returns:
    
    the size of the subsets.
  - compare
```
public int compare(int[] c1,
                   int[] c2)
```
    Specified by:
    
    compare in interface java.util.Comparator<int[]>
    
    Throws:
    
    java.lang.IllegalArgumentException - if the array lengths are not equal to k.
    
    java.lang.IllegalArgumentException - if an element of the array is not within the interval [0, n).