FloatWTables

java.lang.Object
- org.apfloat.internal.FloatElementaryModMath
- - org.apfloat.internal.FloatModMath
  - - org.apfloat.internal.FloatWTables

```
public class FloatWTables
extends FloatModMath
```
Helper class for generating and caching tables of powers of the n:th root of unity.

Since:

1.7.0

Version:

1.9.0

Field Summary

Fields
Modifier and Type Field Description

private static java.util.concurrent.ConcurrentMap<java.util.List<java.lang.Integer>,float[]> cache

Constructor Summary

Constructors
Modifier Constructor Description

private FloatWTables()

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method	Description
`private static FloatModMath`	`getInstance(int modulus)`
`static float[]`	`getInverseWTable(int modulus, int length)`	Get a table of inverses of powers of n:th root of unity.
`static float[]`	`getWTable(int modulus, int length)`	Get a table of powers of n:th root of unity.
`private static float[]`	`getWTable(int modulus, int length, boolean isInverse)`

Methods inherited from class org.apfloat.internal.FloatModMath
createWTable, getForwardNthRoot, getInverseNthRoot, modDivide, modInverse, modPow, negate

Methods inherited from class org.apfloat.internal.FloatElementaryModMath
getModulus, modAdd, modMultiply, modSubtract, setModulus

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

- Field Detail
  - cache
```
private static java.util.concurrent.ConcurrentMap<java.util.List<java.lang.Integer>,float[]> cache
```
- Constructor Detail
  - FloatWTables
```
private FloatWTables()
```
- Method Detail
  - getWTable
```
public static float[] getWTable(int modulus,
                                int length)
```
    Get a table of powers of n:th root of unity.
    
    Parameters:
    
    modulus - The index of the modulus to be used.
    
    length - The length of the table to be returned, i.e. n.
    
    Returns:
    
    The table of powers of the n:th root of unity.
  - getInverseWTable
```
public static float[] getInverseWTable(int modulus,
                                       int length)
```
    Get a table of inverses of powers of n:th root of unity.
    
    Parameters:
    
    modulus - The index of the modulus to be used.
    
    length - The length of the table to be returned, i.e. n.
    
    Returns:
    
    The table of inverses of powers of the n:th root of unity.
  - getWTable
```
private static float[] getWTable(int modulus,
                                 int length,
                                 boolean isInverse)
```
  - getInstance
```
private static FloatModMath getInstance(int modulus)
```