MinHashingTransformer (jaicore-ml 0.1.6 API)

java.lang.Object
- ai.libs.jaicore.ml.core.dataset.attribute.transformer.multivalue.MinHashingTransformer

All Implemented Interfaces:

ISingleAttributeTransformer
```
public class MinHashingTransformer
extends java.lang.Object
implements ISingleAttributeTransformer
```
Converts the sets of multi-value features to short signatures. At first the feature value is transformed into a binaryzation, i.e. a 0/1 Vector, and the MinHashing applied on this vectors afterwards. If two multi-value feature sets are very similar with respect to the Jaccard-Similarity, then the two signatures will be similar as well with a high probability depending on the desired length of the signatures.
For a signature of length n, the same amount of permutations will be created and the n-th element of the signature is determined by the index where the n-th permutation finds the finds the first 1 in the 0/1 Vector.

Constructor Summary

Constructors
Constructor	Description
`MinHashingTransformer(int[][] permutations)`	Constructor where the user gives predefined permutations.
`MinHashingTransformer(int domainSize, int signatureLength, long seed)`	Constructor where suitable permutations are created randomly.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type Method Description

double[] transformAttribute(IAttributeValue<?> attributeToTransform)
- Methods inherited from class java.lang.Object
  clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - MinHashingTransformer
```
public MinHashingTransformer(int[][] permutations)
```
    Constructor where the user gives predefined permutations.
    
    Parameters:
    
    permutations - Predefined permutations. The amount of permutations defines the length of the signature the MinHashing creates and each permutation has to have the length of the domain size.
  - MinHashingTransformer
```
public MinHashingTransformer(int domainSize,
                             int signatureLength,
                             long seed)
```
    Constructor where suitable permutations are created randomly.
    
    Parameters:
    
    domainSize -
    
    signatureLength -
- Method Detail
  - transformAttribute
```
public double[] transformAttribute(IAttributeValue<?> attributeToTransform)
```
    Specified by:
    
    transformAttribute in interface ISingleAttributeTransformer