Module flag4j

Package org.flag4j.arrays.backend

Class PrimitiveDoubleTensorBase<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>>

java.lang.Object

org.flag4j.arrays.backend.AbstractTensor<T,double[],Double>

org.flag4j.arrays.backend.TensorOverSemiRing<T,U,double[],Double>

org.flag4j.arrays.backend.TensorOverRing<T,U,double[],Double>

org.flag4j.arrays.backend.TensorOverField<T,U,double[],Double>

org.flag4j.arrays.backend.DoubleTensorBase<T,U>

Type Parameters:

T - Type of this tensor.

U - Type of dense tensor equivalent to T. If T is dense, then this should be the same type as T. This type parameter is required because some operations (e.g. TensorOverSemiRing.tensorDot(TensorOverSemiRing)) between two sparse tensors result in a dense tensor.

All Implemented Interfaces:

Serializable, TensorBinaryOpsMixin<T,T>, TensorMixin<T,double[],Double>, TensorPrimitiveOpsMixin<T>

Direct Known Subclasses:

CooMatrix, CooTensor, CooVector, CsrMatrix, DensePrimitiveDoubleTensorBase

public abstract class PrimitiveDoubleTensorBase<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>>
extends TensorOverField<T,U,double[],Double>
implements TensorPrimitiveOpsMixin<T>

Base class for all real tensors which are backed by a primitive double array.

The entries of PrimitiveDoubleTensorBase's are mutable but the tensor has a fixed shape.

See Also:

• Serialized Form

Field Summary

Fields inherited from class org.flag4j.arrays.backend.AbstractTensor

entries, rank, shape

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	PrimitiveDoubleTensorBase(Shape shape, double[] entries)	Creates a tensor with the specified entries and shape.

Method Summary

Modifier and Type	Method	Description
T	abs()	Computes the element-wise absolute value of this tensor.
T	add(double b)	Adds a scalar value to each element of this tensor.
T	add(Double b)	Adds a scalar field value to each entry of this tensor.
T	add(T b)	Computes the element-wise sum between two tensors of the same shape.
void	addEq(Double b)	Adds a scalar value to each entry of this tensor and stores the result in this tensor.
T	conj()	Computes the element-wise conjugation of this tensor.
T	copy()	Creates a deep copy of this tensor.
T	div(double divisor)	Computes the scalar division of this tensor and the specified scalar divisor.
T	div(Double b)	Divides each entry of this tensor by a scalar field element.
void	divEq(Double b)	Divides each entry of this tensor by a scalar field element and stores the result in this tensor.
T	elemMult(T b)	Computes the element-wise multiplication of two tensors of the same shape.
T	flatten()	Flattens tensor to single dimension while preserving order of entries.
T	flatten(int axis)	Flattens a tensor along the specified axis.
Double	get(int... indices)	Gets the element of this tensor at the specified indices.
T	H()	Computes the conjugate transpose of a tensor by exchanging the first and last axes of this tensor and conjugating the exchanged values.
T	H(int... axes)	Computes the conjugate transpose of this tensor.
T	H(int axis1, int axis2)	Computes the conjugate transpose of a tensor by conjugating and exchanging axis1 and axis2.
boolean	isOnes()	Checks if this tensor only contains zeros.
boolean	isZeros()	Checks if this tensor only contains zeros.
T	mult(double factor)	Computes the scalar multiplication between this tensor and the specified scalar factor.
T	mult(Double b)	Multiplies a scalar value to each entry of this tensor.
void	multEq(Double b)	Multiplies a scalar value to each entry of this tensor and stores the result in this tensor.
Double	prod()	Computes the product of all values in this tensor.
T	recip()	Computes the element-wise reciprocals of this tensor.
T	reshape(Shape newShape)	Copies and reshapes this tensor.
T	round()	Rounds all entries of this tensor to the nearest whole number.
T	round(int precision)	Rounds all entries of this tensor to the number of decimal specified by precision.
T	sqrt()	Computes the element-wise square root of a tensor.
T	sub(double b)	Subtracts a scalar value from each element of this tensor.
T	sub(Double b)	Subtracts a scalar value from each entry of this tensor.
T	sub(T b)	Computes the element-wise difference between two tensors of the same shape.
void	subEq(Double b)	Subtracts a scalar value from each entry of this tensor and stores the result in this tensor.
Double	sum()	Computes the sum of all values in this tensor.
T	T()	Computes the transpose of a tensor by exchanging the first and last axes of this tensor.
T	tensorTr(int axis1, int axis2)	Computes the generalized trace of this tensor along the specified axes.

Methods inherited from class org.flag4j.arrays.backend.TensorOverSemiRing

tensorDot, tensorDot, tensorDot, tensorDot, tensorTr

Methods inherited from class org.flag4j.arrays.backend.AbstractTensor

getEntries, getRank, getShape, makeLikeTensor, reshape, sameShape, set, totalEntries

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.flag4j.arrays.backend.TensorMixin

T, T

Constructor Details

PrimitiveDoubleTensorBase

protected PrimitiveDoubleTensorBase(Shape shape,
 double[] entries)

Creates a tensor with the specified entries and shape.

Parameters:

shape - Shape of this tensor.

entries - Entries of this tensor. If this tensor is dense, this specifies all entries within the tensor. If this tensor is sparse, this specifies only the non-zero entries of the tensor.

Method Details

get

public Double get(int... indices)

Gets the element of this tensor at the specified indices.

Specified by:

get in interface TensorMixin<T extends PrimitiveDoubleTensorBase<T,U>,double[],Double>

Specified by:

get in class AbstractTensor<T extends PrimitiveDoubleTensorBase<T,U>,double[],Double>

Parameters:

indices - Indices of the element to get.

Returns:

The element of this tensor at the specified indices.

Throws:

ArrayIndexOutOfBoundsException - If any indices are not within this matrix.

flatten

public T flatten()

Flattens tensor to single dimension while preserving order of entries.

Specified by:

flatten in class AbstractTensor<T extends PrimitiveDoubleTensorBase<T,U>,double[],Double>

Returns:

The flattened tensor.

See Also:

• flatten(int)

flatten

public T flatten(int axis)

Flattens a tensor along the specified axis.

Specified by:

flatten in class AbstractTensor<T extends PrimitiveDoubleTensorBase<T,U>,double[],Double>

Parameters:

axis - Axis along which to flatten tensor.

Throws:

ArrayIndexOutOfBoundsException - If the axis is not positive or larger than this.AbstractTensor.getRank()-1.

See Also:

• flatten()

reshape

public T reshape(Shape newShape)

Copies and reshapes this tensor.

Specified by:

reshape in class AbstractTensor<T extends PrimitiveDoubleTensorBase<T,U>,double[],Double>

Parameters:

newShape - New shape for the tensor.

Returns:

A copy of this tensor with the new shape.

Throws:

TensorShapeException - If newShape is not broadcastable to this.shape.

sub

public T sub(Double b)

Subtracts a scalar value from each entry of this tensor.

Specified by:

sub in class TensorOverRing<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Parameters:

b - Scalar value in difference.

Returns:

The difference of this tensor and the scalar b.

subEq

public void subEq(Double b)

Subtracts a scalar value from each entry of this tensor and stores the result in this tensor.

Specified by:

subEq in class TensorOverRing<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Parameters:

b - Scalar value in difference.

add

public T add(Double b)

Adds a scalar field value to each entry of this tensor.

Specified by:

add in class TensorOverSemiRing<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Parameters:

b - Scalar field value in sum.

Returns:

The sum of this tensor with the scalar b.

addEq

public void addEq(Double b)

Adds a scalar value to each entry of this tensor and stores the result in this tensor.

Specified by:

addEq in class TensorOverSemiRing<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Parameters:

b - Scalar field value in sum.

add

public T add(T b)

Computes the element-wise sum between two tensors of the same shape.

Specified by:

add in class TensorOverSemiRing<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Parameters:

b - Second tensor in the element-wise sum.

Returns:

The sum of this tensor with b.

Throws:

IllegalArgumentException - If this tensor and b do not have the same shape.

mult

public T mult(Double b)

Multiplies a scalar value to each entry of this tensor.

Specified by:

mult in class TensorOverSemiRing<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Parameters:

b - Scalar value in product.

Returns:

The product of this tensor with b.

multEq

public void multEq(Double b)

Multiplies a scalar value to each entry of this tensor and stores the result in this tensor.

Specified by:

multEq in class TensorOverSemiRing<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Parameters:

b - Scalar value in product.

sub

public T sub(T b)

Computes the element-wise difference between two tensors of the same shape.

Specified by:

sub in class TensorOverRing<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Parameters:

b - Second tensor in the element-wise difference.

Returns:

The difference of this tensor with b.

Throws:

IllegalArgumentException - If this tensor and b do not have the same shape.

abs

public T abs()

Computes the element-wise absolute value of this tensor.

Specified by:

abs in class TensorOverRing<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Returns:

The element-wise absolute value of this tensor.

elemMult

public T elemMult(T b)

Computes the element-wise multiplication of two tensors of the same shape.

Specified by:

elemMult in class TensorOverSemiRing<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Parameters:

b - Second tensor in the element-wise product.

Returns:

The element-wise product between this tensor and b.

Throws:

IllegalArgumentException - If this tensor and b do not have the same shape.

tensorTr

public T tensorTr(int axis1,
 int axis2)

Computes the generalized trace of this tensor along the specified axes.

The generalized tensor trace is the sum along the diagonal values of the 2D sub-arrays_old of this tensor specified by axis1 and axis2. The shape of the resulting tensor is equal to this tensor with the axis1 and axis2 removed.

Specified by:

tensorTr in class TensorOverSemiRing<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Parameters:

axis1 - First axis for 2D sub-array.

axis2 - Second axis for 2D sub-array.

Returns:

The generalized trace of this tensor along axis1 and axis2. This will be a tensor of rank this.getRank() - 2 with the same shape as this tensor but with axis1 and axis2 removed.

Throws:

IndexOutOfBoundsException - If the two axes are not both larger than zero and less than this tensors rank.

IllegalArgumentException - If axis1 == @code axis2 or this.shape.get(axis1) != this.shape.get(axis1) (i.e. the axes are equal or the tensor does not have the same length along the two axes.)

isZeros

public boolean isZeros()

Checks if this tensor only contains zeros.

Specified by:

isZeros in class TensorOverSemiRing<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Returns:

True if this tensor only contains zeros. Otherwise, returns false.

isOnes

public boolean isOnes()

Checks if this tensor only contains zeros. If this tensor is sparse, then only the non-zero values are considered.

Specified by:

isOnes in class TensorOverSemiRing<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Returns:

True if this tensor only contains zeros. Otherwise, returns false.

sum

public Double sum()

Computes the sum of all values in this tensor.

Specified by:

sum in class TensorOverSemiRing<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Returns:

The sum of all values in this tensor.

prod

public Double prod()

Computes the product of all values in this tensor.

Specified by:

prod in class TensorOverSemiRing<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Returns:

The product of all values in this tensor.

sqrt

public T sqrt()

Computes the element-wise square root of a tensor.

Specified by:

sqrt in class TensorOverField<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Returns:

The result of applying an element-wise square root to this tensor. Note, this method will compute the principle square root i.e. the square root with positive real part.

T

public T T()

Computes the transpose of a tensor by exchanging the first and last axes of this tensor.

Specified by:

T in interface TensorMixin<T extends PrimitiveDoubleTensorBase<T,U>,double[],Double>

Returns:

The transpose of this tensor.

See Also:

• TensorMixin.T(int, int)
• TensorMixin.T(int...)

conj

public T conj()

Computes the element-wise conjugation of this tensor.

Specified by:

conj in class TensorOverRing<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Returns:

The element-wise conjugation of this tensor.

H

public T H()

Computes the conjugate transpose of a tensor by exchanging the first and last axes of this tensor and conjugating the exchanged values.

Specified by:

H in class TensorOverRing<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Returns:

The conjugate transpose of this tensor.

See Also:

• H(int, int)
• H(int...)

H

public T H(int axis1,
 int axis2)

Computes the conjugate transpose of a tensor by conjugating and exchanging axis1 and axis2.

Specified by:

H in class TensorOverRing<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Parameters:

axis1 - First axis to exchange and conjugate.

axis2 - Second axis to exchange and conjugate.

Returns:

The conjugate transpose of this tensor according to the specified axes.

Throws:

IndexOutOfBoundsException - If either axis1 or axis2 are out of bounds for the rank of this tensor.

See Also:

• H()
• H(int...)

H

public T H(int... axes)

Computes the conjugate transpose of this tensor. That is, conjugates and permutes the axes of this tensor so that it matches the permutation specified by axes.

Specified by:

H in class TensorOverRing<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Parameters:

axes - Permutation of tensor axis. If the tensor has rank N, then this must be an array of length N which is a permutation of {0, 1, 2, ..., N-1}.

Returns:

The conjugate transpose of this tensor with its axes permuted by the axes array.

Throws:

IndexOutOfBoundsException - If any element of axes is out of bounds for the rank of this tensor.

IllegalArgumentException - If axes is not a permutation of {1, 2, 3, ... N-1}.

See Also:

• H(int, int)
• H()

recip

public T recip()

Computes the element-wise reciprocals of this tensor.

Specified by:

recip in class TensorOverField<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Returns:

A tensor containing the reciprocal elements of this tensor.

div

public T div(Double b)

Divides each entry of this tensor by a scalar field element.

Specified by:

div in class TensorOverField<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Parameters:

b - Scalar field value in quotient.

Returns:

The quotient of this tensor with b.

divEq

public void divEq(Double b)

Divides each entry of this tensor by a scalar field element and stores the result in this tensor.

Specified by:

divEq in class TensorOverField<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Parameters:

b - Scalar field value in quotient.

copy

public T copy()

Creates a deep copy of this tensor.

Specified by:

copy in interface TensorMixin<T extends PrimitiveDoubleTensorBase<T,U>,double[],Double>

Returns:

A deep copy of this tensor.

add

public T add(double b)

Adds a scalar value to each element of this tensor.

Specified by:

add in interface TensorPrimitiveOpsMixin<T extends PrimitiveDoubleTensorBase<T,U>>

Specified by:

add in class TensorOverField<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Parameters:

b - Value to add to each entry of this tensor.

Returns:

The result of adding the specified scalar value to each entry of this tensor.

sub

public T sub(double b)

Subtracts a scalar value from each element of this tensor.

Specified by:

sub in interface TensorPrimitiveOpsMixin<T extends PrimitiveDoubleTensorBase<T,U>>

Specified by:

sub in class TensorOverField<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Parameters:

b - Value to subtract from each entry of this tensor.

Returns:

The result of subtracting the specified scalar value from each entry of this tensor.

mult

public T mult(double factor)

Computes the scalar multiplication between this tensor and the specified scalar factor.

Specified by:

mult in interface TensorPrimitiveOpsMixin<T extends PrimitiveDoubleTensorBase<T,U>>

Specified by:

mult in class TensorOverField<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Parameters:

factor - Scalar factor to apply to this tensor.

Returns:

The scalar product of this tensor and factor.

div

public T div(double divisor)

Computes the scalar division of this tensor and the specified scalar divisor.

Specified by:

div in interface TensorPrimitiveOpsMixin<T extends PrimitiveDoubleTensorBase<T,U>>

Specified by:

div in class TensorOverField<T extends PrimitiveDoubleTensorBase<T,U>,U extends PrimitiveDoubleTensorBase<U,U>,double[],Double>

Parameters:

divisor - The scalar value to divide this tensor by.

Returns:

The result of dividing this tensor by the specified scalar.

round

public T round()

Rounds all entries of this tensor to the nearest whole number.

Returns:

A copy of this tensor with all entries rounded to the nearest whole number.

See Also:

• round(int)

round

public T round(int precision)

Rounds all entries of this tensor to the number of decimal specified by precision.

Parameters:

precision - The number of decimal places to round the tensor to.

Returns:

A copy of this tensor with all entries rounded to the number of decimal specified by precision.

See Also:

• round()