Package org.flag4j.operations.common.complex

Class ComplexOperations

java.lang.Object

org.flag4j.operations.common.complex.ComplexOperations

public class ComplexOperations
extends Object

This class provides low level methods for computing operations on real tensors. These methods can be applied to either sparse or dense real tensors.

Constructor Summary

Constructors

Modifier	Constructor	Description
private	ComplexOperations()

Method Summary

Modifier and Type	Method	Description
static double[]	abs(CNumber[] src)	Computes the element-wise absolute value of a tensor.
static CNumber[]	conj(CNumber[] src)	Computes the element-wise complex conjugate of a tensor.
static CNumber[]	round(CNumber[] src)	Rounds the values of a tensor to the nearest integer.
static CNumber[]	round(CNumber[] src, int precision)	Rounds the values of a tensor with specified precision.
static CNumber[]	roundToZero(CNumber[] src, double threshold)	Rounds values which are close to zero in absolute value to zero.
static CNumber[]	scalDiv(double[] entries, CNumber divisor)	Computes the scalar division of a tensor.
static CNumber[]	scalMult(double[] entries, CNumber factor)	Computes the scalar multiplication of a tensor.
static CNumber[]	scalMult(CNumber[] src, double factor)	Computes the scalar multiplication of a tensor with a scalar value.
static CNumber[]	scalMult(CNumber[] src, CNumber factor)	Computes the scalar multiplication of a tensor with a scalar value.
static CNumber[]	scalMult(CNumber[] src, CNumber[] dest, CNumber factor)	Computes the scalar multiplication of a tensor.
static CNumber[]	scalMult(CNumber[] src, CNumber[] dest, CNumber factor, int start, int stop)	Computes the scalar multiplication of a tensor.
static CNumber[]	sqrt(double[] src)	Computes the element-wise square root of a tensor.
static CNumber[]	sqrt(CNumber[] src)	Computes the element-wise square root of a tensor.
static double[]	toReal(CNumber[] src)	Converts a complex tensor to a real tensor by copying the real component and discarding the imaginary component.

Methods inherited from class java.lang.Object

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

Constructor Details

ComplexOperations

private ComplexOperations()

Method Details

sqrt

public static CNumber[] sqrt(CNumber[] src)

Computes the element-wise square root of a tensor.

Parameters:

src - Elements of the tensor.

Returns:

The element-wise square root of the tensor.

sqrt

public static CNumber[] sqrt(double[] src)

Computes the element-wise square root of a tensor.

Parameters:

src - Elements of the tensor.

Returns:

The element-wise square root of the tensor.

abs

public static double[] abs(CNumber[] src)

Computes the element-wise absolute value of a tensor.

Parameters:

src - Elements of the tensor.

Returns:

The element-wise absolute value of the tensor.

round

public static CNumber[] round(CNumber[] src)

Rounds the values of a tensor to the nearest integer. Also see round(CNumber[], int).

Parameters:

src - Entries of the tensor to round.

Returns:

The result of rounding all entries of the source tensor to the nearest integer.

Throws:

IllegalArgumentException - If precision is negative.

round

public static CNumber[] round(CNumber[] src,
 int precision)

Rounds the values of a tensor with specified precision. Note, if precision is zero, round(CNumber[]) is preferred.

Parameters:

src - Entries of the tensor to round.

precision - Precision to round to (i.e. the number of decimal places).

Returns:

The result of rounding all entries of the source tensor with the specified precision.

Throws:

IllegalArgumentException - If precision is negative.

roundToZero

public static CNumber[] roundToZero(CNumber[] src,
 double threshold)

Rounds values which are close to zero in absolute value to zero.

Parameters:

threshold - Threshold for rounding values to zero. That is, if a value in this tensor is less than the threshold in absolute value then it will be rounded to zero. This value must be non-negative.

Returns:

A copy of this matrix with rounded values.

Throws:

IllegalArgumentException - If threshold is negative.

scalMult

public static CNumber[] scalMult(CNumber[] src,
 double factor)

Computes the scalar multiplication of a tensor with a scalar value.

Parameters:

src - Entries of the tensor.

factor - Scalar value.

Returns:

The result of the scalar multiplication of a tensor.

scalMult

public static CNumber[] scalMult(CNumber[] src,
 CNumber factor)

Computes the scalar multiplication of a tensor with a scalar value.

Parameters:

src - Entries of the tensor.

factor - Scalar value.

Returns:

The result of the scalar multiplication of a tensor.

scalMult

public static CNumber[] scalMult(double[] entries,
 CNumber factor)

Computes the scalar multiplication of a tensor.

Parameters:

entries - Entries of the tensor.

factor - Scalar value to multiply.

Returns:

The scalar multiplication of the tensor.

scalMult

public static CNumber[] scalMult(CNumber[] src,
 CNumber[] dest,
 CNumber factor)

Computes the scalar multiplication of a tensor.

Parameters:

src - Entries of the tensor.

dest - Array to store result in. May be null.

factor - Scalar value to multiply.

Returns:

A reference to the dest array if it was not null. Otherwise, a new array will be formed.

Throws:

ArrayIndexOutOfBoundsException - If dest is not at least the size of src.

scalMult

public static CNumber[] scalMult(CNumber[] src,
 CNumber[] dest,
 CNumber factor,
 int start,
 int stop)

Computes the scalar multiplication of a tensor.

Parameters:

src - Entries of the tensor.

dest - Array to store result in. May be null.

factor - Scalar value to multiply.

start - Starting index of scalar multiplication.

stop - Stopping index of scalar multiplication.

Returns:

A reference to the dest array if it was not null. Otherwise, a new array will be formed.

Throws:

ArrayIndexOutOfBoundsException - If dest is not the size of src.

scalDiv

public static CNumber[] scalDiv(double[] entries,
 CNumber divisor)

Computes the scalar division of a tensor.

Parameters:

entries - Entries of the tensor.

divisor - Scalar value to divide each element ot the tensor by.

Returns:

The scalar division of the tensor.

conj

public static CNumber[] conj(CNumber[] src)

Computes the element-wise complex conjugate of a tensor.

Parameters:

src - Entries of the tensor.

Returns:

The element-wise complex conjugate of the tensor

toReal

public static double[] toReal(CNumber[] src)

Converts a complex tensor to a real tensor by copying the real component and discarding the imaginary component.

Parameters:

src - Entries of complex tensor.

Returns:

Equivalent real entries for complex tensor.