xal.tools.math

Class DifferentialVariable

java.lang.Object

xal.tools.math.DifferentialVariable

public class DifferentialVariable
extends java.lang.Object

Represents an immutable value and its differentials relative to independent variables and performs math operations on them in support of error propagation.

Field Summary

Fields

Modifier and Type	Field and Description
static DifferentialVariable	ONE representation of the constant one
static DifferentialVariable	ZERO representation of the constant zero

Constructor Summary

Constructors

Constructor and Description
DifferentialVariable(double value, int offset, double... derivatives) Primary Constructor

Method Summary

Modifier and Type	Method and Description
DifferentialVariable	abs() get the absolute value of this variable
DifferentialVariable	acos() get the arc cosine of this variable
static DifferentialVariable	add(DifferentialVariable... addends) perform the addition operation between two variables
static DifferentialVariable	add(DifferentialVariable variable, double value) perform the addition operation between a variable and a scalar value
static DifferentialVariable	add(double value, DifferentialVariable variable) perform the addition operation between a variable and a scalar value
DifferentialVariable	asin() get the arc sine of this variable
DifferentialVariable	atan() get the arc tangent of this variable
DifferentialVariable	cos() get the cosine of this variable
DifferentialVariable	cosh() get the hyperbolic cosine of this variable
static DifferentialVariable	divide(DifferentialVariable dividend, DifferentialVariable divisor) divide the dividend by the divisor
static DifferentialVariable	divide(DifferentialVariable variable, double value) divide the variable by the scalar value
static DifferentialVariable	divide(double value, DifferentialVariable variable) divide the scalar value by the variable
DifferentialVariable	exp() get the exponential (base e) of this variable
double	getDerivative(int index) get the derivative for the independent variable at the specified index
static DifferentialVariable	getInstance(double value, double... derivatives) Constructor with zero offset
double	getValue() get the value
DifferentialVariable	log() get the natural logarithm (base e) of this variable
DifferentialVariable	minus(DifferentialVariable subtrahend) subtract the specified subtrahend from this variable
DifferentialVariable	minus(double subtrahend) subtract the specified subtrahend from this variable
static DifferentialVariable	multiply(DifferentialVariable... multiplicands) multiply the variables
static DifferentialVariable	multiply(DifferentialVariable variable, double value) perform the multiplication operation between a variable and a scalar value
static DifferentialVariable	multiply(double value, DifferentialVariable variable) perform the multiplication operation between a variable and a scalar value
DifferentialVariable	negate() negate the variable
static DifferentialVariable	newConstant(double value) get a constant value
DifferentialVariable	over(DifferentialVariable divisor) divide this variable by the specified divisor
DifferentialVariable	over(double divisor) divide this variable by the specified divisor
DifferentialVariable	plus(DifferentialVariable addend) add this variable to the specified addend
DifferentialVariable	plus(double addend) add this variable to the specified addend
DifferentialVariable	pow(double power) raise this variable to the specified power
DifferentialVariable	reciprocal() calculate and return the reciprocol of this variable
DifferentialVariable	sin() get the sine of this variable
DifferentialVariable	sinh() get the hyperbolic sine of this variable
DifferentialVariable	sqrt() get the square root of this variable
static DifferentialVariable	subtract(DifferentialVariable minuend, DifferentialVariable subtrahend) subtract the subtrahend variable from the minuend variable
static DifferentialVariable	subtract(DifferentialVariable variable, double subtrahend) subtract the scalar value from the variable
static DifferentialVariable	subtract(double value, DifferentialVariable variable) subtract the variable from the scalar value
DifferentialVariable	tan() get the tangent of this variable
DifferentialVariable	tanh() get the hyperbolic tangent of this variable
DifferentialVariable	times(DifferentialVariable multiplicand) multiply this variable by the specified multiplicand
DifferentialVariable	times(double multiplicand) multiply this variable by the specified multiplicand
double	varianceWithSignalVariance(double commonVariance) calculate the variance for this variable given a common variance for each independent variable
double	varianceWithSignalVariances(double... variances) calculate the variance for this variable given variances for all independent variables
double	varianceWithSignalVariances(int offset, double... variances) calculate the variance for this variable given the independent variables starting at the specified offset among all independent variables

Methods inherited from class java.lang.Object

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

Field Detail

ZERO

public static final DifferentialVariable ZERO

representation of the constant zero

ONE

public static final DifferentialVariable ONE

representation of the constant one

Constructor Detail

DifferentialVariable

public DifferentialVariable(double value,
                            int offset,
                            double... derivatives)

Primary Constructor

Parameters:

value - the value of the variable

offset - offset of this differential's first independent variable relative to all independent variables

derivatives - array of derivatives beginning with this differential's first independent variable

Method Detail

getInstance

public static DifferentialVariable getInstance(double value,
                                               double... derivatives)

Constructor with zero offset

Parameters:

value - the value of the variable

derivatives - array of derivatives beginning with the first independent variable

newConstant

public static DifferentialVariable newConstant(double value)

get a constant value

getValue

public double getValue()

get the value

getDerivative

public double getDerivative(int index)

get the derivative for the independent variable at the specified index

varianceWithSignalVariance

public double varianceWithSignalVariance(double commonVariance)

calculate the variance for this variable given a common variance for each independent variable

varianceWithSignalVariances

public double varianceWithSignalVariances(double... variances)

calculate the variance for this variable given variances for all independent variables

varianceWithSignalVariances

public double varianceWithSignalVariances(int offset,
                                          double... variances)

calculate the variance for this variable given the independent variables starting at the specified offset among all independent variables

add

public static DifferentialVariable add(DifferentialVariable variable,
                                       double value)

perform the addition operation between a variable and a scalar value

add

public static DifferentialVariable add(double value,
                                       DifferentialVariable variable)

perform the addition operation between a variable and a scalar value

add

public static DifferentialVariable add(DifferentialVariable... addends)

perform the addition operation between two variables

subtract

public static DifferentialVariable subtract(DifferentialVariable variable,
                                            double subtrahend)

subtract the scalar value from the variable

subtract

public static DifferentialVariable subtract(double value,
                                            DifferentialVariable variable)

subtract the variable from the scalar value

subtract

public static DifferentialVariable subtract(DifferentialVariable minuend,
                                            DifferentialVariable subtrahend)

subtract the subtrahend variable from the minuend variable

multiply

public static DifferentialVariable multiply(DifferentialVariable variable,
                                            double value)

perform the multiplication operation between a variable and a scalar value

multiply

public static DifferentialVariable multiply(double value,
                                            DifferentialVariable variable)

perform the multiplication operation between a variable and a scalar value

multiply

public static DifferentialVariable multiply(DifferentialVariable... multiplicands)

multiply the variables

divide

public static DifferentialVariable divide(DifferentialVariable variable,
                                          double value)

divide the variable by the scalar value

divide

public static DifferentialVariable divide(double value,
                                          DifferentialVariable variable)

divide the scalar value by the variable

divide

public static DifferentialVariable divide(DifferentialVariable dividend,
                                          DifferentialVariable divisor)

divide the dividend by the divisor

negate

public DifferentialVariable negate()

negate the variable

reciprocal

public DifferentialVariable reciprocal()

calculate and return the reciprocol of this variable

plus

public DifferentialVariable plus(double addend)

add this variable to the specified addend

plus

public DifferentialVariable plus(DifferentialVariable addend)

add this variable to the specified addend

minus

public DifferentialVariable minus(double subtrahend)

subtract the specified subtrahend from this variable

minus

public DifferentialVariable minus(DifferentialVariable subtrahend)

subtract the specified subtrahend from this variable

times

public DifferentialVariable times(double multiplicand)

multiply this variable by the specified multiplicand

times

public DifferentialVariable times(DifferentialVariable multiplicand)

multiply this variable by the specified multiplicand

over

public DifferentialVariable over(double divisor)

divide this variable by the specified divisor

over

public DifferentialVariable over(DifferentialVariable divisor)

divide this variable by the specified divisor

pow

public final DifferentialVariable pow(double power)

raise this variable to the specified power

sqrt

public final DifferentialVariable sqrt()

get the square root of this variable

abs

public final DifferentialVariable abs()

get the absolute value of this variable

log

public final DifferentialVariable log()

get the natural logarithm (base e) of this variable

exp

public final DifferentialVariable exp()

get the exponential (base e) of this variable

sin

public final DifferentialVariable sin()

get the sine of this variable

cos

public final DifferentialVariable cos()

get the cosine of this variable

tan

public final DifferentialVariable tan()

get the tangent of this variable

asin

public final DifferentialVariable asin()

get the arc sine of this variable

acos

public final DifferentialVariable acos()

get the arc cosine of this variable

atan

public final DifferentialVariable atan()

get the arc tangent of this variable

sinh

public final DifferentialVariable sinh()

get the hyperbolic sine of this variable

cosh

public final DifferentialVariable cosh()

get the hyperbolic cosine of this variable

tanh

public final DifferentialVariable tanh()

get the hyperbolic tangent of this variable