TensorStream

java.lang.Object
- edu.stanford.math.plex4.streams.derived.TensorStream<T,U>

Type Parameters:
T - the underlying basis type of the first chain complex
U - the underlying basis type of the second chain complex

All Implemented Interfaces:

AbstractFilteredStream<edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>>, java.lang.Iterable<edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>>

Direct Known Subclasses:

HomStream
```
public class TensorStream<T,U>
extends java.lang.Object
implements AbstractFilteredStream<edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>>
```
This implements the tensor product of two filtered chain complexes. For the definition of the tensor product of complexes, one is invited to consult any standard textbook on algebraic topology or homological algebra. Note that we define the filtration index for a tensor product pair to be the maximum of the filtration indices of its components. This definition was chosen since it was the only definition that makes sense - a pair comes into existence exactly when both components have come into existence.

Author:

Andrew Tausz

Field Summary

Fields
Modifier and Type	Field and Description
`protected AbstractFilteredStream<T>`	`stream1` The first factor in the tensor product.
`protected AbstractFilteredStream<U>`	`stream2` The second factor in the tensor product.

Constructor Summary

Constructors
Constructor and Description
`TensorStream(AbstractFilteredStream<T> stream1, AbstractFilteredStream<U> stream2)` This constructor initializes the stream from two underlying filtered chain complexes.

Method Summary

Methods
Modifier and Type	Method and Description
`boolean`	`containsElement(edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U> basisElement)` This function returns whether an element is contained in the stream.
`void`	`finalizeStream()` This function prepares the stream for use by a consumer, such as the PersistentHomology class.
`java.util.Comparator<edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>>`	`getBasisComparator()` This function returns a comparator on the underlying basis type.
`edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>[]`	`getBoundary(edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U> basisElement)` This function returns the elements in the boundary of the supplied basisElement, without the coefficients.
`int[]`	`getBoundaryCoefficients(edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U> basisElement)` This function returns the coefficients of the boundary of the supplied basis element.
`int`	`getDimension(edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U> basisElement)` This function returns the dimension of a basis element within the chain complex.
`int`	`getFiltrationIndex(edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U> basisElement)` This function returns the filtration index of the requested basis element.
`double`	`getFiltrationValue(edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U> basisElement)`
`int`	`getMaximumFiltrationIndex()` This function gets the maximum filtration index in the complex.
`int`	`getMinimumFiltrationIndex()` This function gets the minimum filtration index in the complex.
`int`	`getSize()` This function returns the total number of elements in the stream.
`boolean`	`isFinalized()` This function checks whether the finalize() function has been called.
`java.util.Iterator<edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>>`	`iterator()`
`<G> PersistenceInvariantDescriptor<Interval<java.lang.Double>,G>`	`transform(PersistenceInvariantDescriptor<Interval<java.lang.Integer>,G> barcodeCollection)` This function transforms the given collection of filtration index barcodes into filtration value barcodes.

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

- Field Detail
  - stream1
```
protected final AbstractFilteredStream<T> stream1
```
    The first factor in the tensor product.
  - stream2
```
protected final AbstractFilteredStream<U> stream2
```
    The second factor in the tensor product.
- Constructor Detail
  - TensorStream
```
public TensorStream(AbstractFilteredStream<T> stream1,
            AbstractFilteredStream<U> stream2)
```
    This constructor initializes the stream from two underlying filtered chain complexes.
    
    Parameters:
    stream1 - the first chain complex
    stream2 - the second chain complex
- Method Detail
  - getBoundary
```
public edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>[] getBoundary(edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U> basisElement)
```
    Description copied from interface: AbstractFilteredStream
    
    This function returns the elements in the boundary of the supplied basisElement, without the coefficients. We do not integrate the elements of the boundary array with their respective coefficients since this interface is designed to be independent of the algebraic environment.
    
    Specified by:
    
    getBoundary in interface AbstractFilteredStream<edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>>
    
    Parameters:
    basisElement - the element to get the boundary of
    
    Returns:
    an array containing the boundary elements of the queried element
  - getBoundaryCoefficients
```
public int[] getBoundaryCoefficients(edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U> basisElement)
```
    Description copied from interface: AbstractFilteredStream
    
    This function returns the coefficients of the boundary of the supplied basis element. Note that in many cases, this will be the standard array consisting of alternating signs: [1, -1, 1, -1, ...]. However, this will not always be the case. Thus this must be left abstract. Also note that the coefficients will always be integers.
    
    Specified by:
    
    getBoundaryCoefficients in interface AbstractFilteredStream<edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>>
    
    Parameters:
    basisElement - the element to get the boundary coefficients of
    
    Returns:
    an array containing the boundary coefficients of the queried element
  - getDimension
```
public int getDimension(edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U> basisElement)
```
    Description copied from interface: AbstractFilteredStream
    
    This function returns the dimension of a basis element within the chain complex.
    
    Specified by:
    
    getDimension in interface AbstractFilteredStream<edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>>
    
    Parameters:
    basisElement - the element to get the dimension of
    
    Returns:
    the dimension of the basis element within the chain complex
  - iterator
```
public java.util.Iterator<edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>> iterator()
```
    Specified by:
    
    iterator in interface java.lang.Iterable<edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>>
  - getFiltrationIndex
```
public int getFiltrationIndex(edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U> basisElement)
```
    Description copied from interface: AbstractFilteredStream
    
    This function returns the filtration index of the requested basis element.
    
    Specified by:
    
    getFiltrationIndex in interface AbstractFilteredStream<edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>>
    
    Parameters:
    basisElement - the basis element to get the filtration index for
    
    Returns:
    the filtration index of the specified basis element
  - getFiltrationValue
```
public double getFiltrationValue(edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U> basisElement)
```
    Specified by:
    
    getFiltrationValue in interface AbstractFilteredStream<edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>>
  - containsElement
```
public boolean containsElement(edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U> basisElement)
```
    Description copied from interface: AbstractFilteredStream
    
    This function returns whether an element is contained in the stream.
    
    Specified by:
    
    containsElement in interface AbstractFilteredStream<edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>>
    
    Parameters:
    basisElement - the basis element to be tested
  - finalizeStream
```
public void finalizeStream()
```
    Description copied from interface: AbstractFilteredStream
    
    This function prepares the stream for use by a consumer, such as the PersistentHomology class. After finalization, the stream cannot not be modified by adding or removing elements. In practice, the finalize procedure will probably do some sorting and construction of data structures necessary for iterating through the stream.
    
    Specified by:
    
    finalizeStream in interface AbstractFilteredStream<edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>>
  - isFinalized
```
public boolean isFinalized()
```
    Description copied from interface: AbstractFilteredStream
    
    This function checks whether the finalize() function has been called.
    
    Specified by:
    
    isFinalized in interface AbstractFilteredStream<edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>>
    
    Returns:
    true if the stream has been finalized, and false otherwise
  - getSize
```
public int getSize()
```
    Description copied from interface: AbstractFilteredStream
    
    This function returns the total number of elements in the stream.
    
    Specified by:
    
    getSize in interface AbstractFilteredStream<edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>>
    
    Returns:
    the size of the stream
  - getMaximumFiltrationIndex
```
public int getMaximumFiltrationIndex()
```
    Description copied from interface: AbstractFilteredStream
    
    This function gets the maximum filtration index in the complex.
    
    Specified by:
    
    getMaximumFiltrationIndex in interface AbstractFilteredStream<edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>>
    
    Returns:
    the maximum filtration index
  - getMinimumFiltrationIndex
```
public int getMinimumFiltrationIndex()
```
    Description copied from interface: AbstractFilteredStream
    
    This function gets the minimum filtration index in the complex.
    
    Specified by:
    
    getMinimumFiltrationIndex in interface AbstractFilteredStream<edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>>
    
    Returns:
    the minimum filtration index
  - getBasisComparator
```
public java.util.Comparator<edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>> getBasisComparator()
```
    Description copied from interface: AbstractFilteredStream
    
    This function returns a comparator on the underlying basis type.
    
    Specified by:
    
    getBasisComparator in interface AbstractFilteredStream<edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>>
    
    Returns:
    a comparator on the underlying basis type
  - transform
```
public <G> PersistenceInvariantDescriptor<Interval<java.lang.Double>,G> transform(PersistenceInvariantDescriptor<Interval<java.lang.Integer>,G> barcodeCollection)
```
    Description copied from interface: AbstractFilteredStream
    
    This function transforms the given collection of filtration index barcodes into filtration value barcodes.
    
    Specified by:
    
    transform in interface AbstractFilteredStream<edu.stanford.math.primitivelib.autogen.pair.ObjectObjectPair<T,U>>
    
    Parameters:
    barcodeCollection - the set of filtration index barcodes
    
    Returns:
    the barcodes transformed into filtration value form

Class TensorStream<T,U>

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

stream1

stream2

Constructor Detail

TensorStream

Method Detail

getBoundary

getBoundaryCoefficients

getDimension

iterator

getFiltrationIndex

getFiltrationValue

containsElement

finalizeStream

isFinalized

getSize

getMaximumFiltrationIndex

getMinimumFiltrationIndex

getBasisComparator

transform