uk.ac.starlink.ttools.plot2.geom

Class TimeJELFunction

java.lang.Object

uk.ac.starlink.ttools.plot2.geom.TimeJELFunction

All Implemented Interfaces:

java.util.function.DoubleUnaryOperator

public class TimeJELFunction
extends Object
implements java.util.function.DoubleUnaryOperator

Function operating on a time value as used in a Time plot. The input value of the function is in unix seconds. A number of variables representing time and based on that input value are available, currently: "mjd", "jd", "unixSec" and "decYear". Typically the expression will simply be one of these terms.

Since:

15 Dec 2022

Author:

Mark Taylor

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	TimeJELFunction.TimeQuantity Defines a quantity representing time that can be used in expressions supplied to this class.
static class	TimeJELFunction.TimeResolver This public class is an implementation detail, not intended for external use.

Constructor Summary

Constructors

Constructor and Description
TimeJELFunction(String fexpr) Constructor.

Method Summary

Modifier and Type	Method and Description
double	applyAsDouble(double unixSec) Function of time in seconds since the Unix epoch.
String	getExpression() Returns the text of the function expression.
static TimeJELFunction.TimeQuantity[]	getTimeQuantities() Returns a list of TimeQuantity objects that can be referred to by name from expressions used by this class.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.function.DoubleUnaryOperator

andThen, compose, identity

Constructor Detail

TimeJELFunction

public TimeJELFunction(String fexpr)
                throws gnu.jel.CompilationException

Constructor.

Parameters:

fexpr - JEL expression in terms of a time variable

Throws:

gnu.jel.CompilationException

Method Detail

applyAsDouble

public double applyAsDouble(double unixSec)

Function of time in seconds since the Unix epoch.

Specified by:

applyAsDouble in interface java.util.function.DoubleUnaryOperator

Parameters:

unixSec - unix seconds

Returns:

time representation as defined by this function

getExpression

public String getExpression()

Returns the text of the function expression.

Returns:

function expression

getTimeQuantities

public static TimeJELFunction.TimeQuantity[] getTimeQuantities()

Returns a list of TimeQuantity objects that can be referred to by name from expressions used by this class.

Returns:

ordered list of time quantities