Package org.djunits.quantity

Class Speed

java.lang.Object

java.lang.Number

org.djunits.quantity.def.Quantity<Speed,Speed.Unit>

org.djunits.quantity.Speed

All Implemented Interfaces:

Serializable, Comparable<Speed>, Additive<Speed>, Scalable<Speed>, Value<Speed.Unit,Speed>

public class Speed
extends Quantity<Speed,Speed.Unit>

Speed is the rate of change of position over time.

Copyright (c) 2025-2026 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved. See for project information https://djunits.org. The DJUNITS project is distributed under a three-clause BSD-style license.

Author:

Alexander Verbraeck

See Also:

• Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Speed.Unit	Speed.Unit encodes the units of the rate of change of a position over time.

Field Summary

Fields

Modifier and Type	Field	Description
static final Speed	NaN	Constant with value NaN.
static final Speed	NEG_MAXVALUE	Constant with value -MAX_VALUE.
static final Speed	NEGATIVE_INFINITY	Constant with value NEGATIVE_INFINITY.
static final Speed	ONE	Constant with value one.
static final Speed	POS_MAXVALUE	Constant with value MAX_VALUE.
static final Speed	POSITIVE_INFINITY	Constant with value POSITIVE_INFINITY.
static final Speed	ZERO	Constant with value zero.

Constructor Summary

Constructors

Constructor	Description
Speed(double value, String abbreviation)	Instantiate a Speed quantity with a unit, expressed as a String.
Speed(double value, Speed.Unit unit)	Instantiate a Speed quantity with a unit.
Speed(Speed value)	Construct Speed quantity.

Method Summary

Modifier and Type	Method	Description
final Duration	divide(Acceleration v)	Calculate the division of Speed and Acceleration, which results in a Duration scalar.
final Acceleration	divide(Duration v)	Calculate the division of Speed and Duration, which results in a Acceleration scalar.
final Length	divide(Frequency v)	Calculate the division of Speed and Frequency, which results in a Length scalar.
final Frequency	divide(Length v)	Calculate the division of Speed and Length, which results in a Frequency scalar.
final Dimensionless	divide(Speed v)	Calculate the division of Speed and Speed, which results in a Dimensionless scalar.
Speed	instantiate(double si)	Instantiate a quantity with an SI or base value.
final FlowVolume	multiply(Area v)	Calculate the multiplication of Speed and Area, which results in a FlowVolume scalar.
final Length	multiply(Duration v)	Calculate the multiplication of Speed and Duration, which results in a Length scalar.
final Force	multiply(FlowMass v)	Calculate the multiplication of Speed and FlowMass, which results in a Force scalar.
final Power	multiply(Force v)	Calculate the multiplication of Speed and Force, which results in a Power scalar.
final Acceleration	multiply(Frequency v)	Calculate the multiplication of Speed and Frequency, which results in a Acceleration scalar.
final Frequency	multiply(LinearObjectDensity v)	Calculate the multiplication of Speed and LinearObjectDensity, which results in a Frequency scalar.
final Momentum	multiply(Mass v)	Calculate the multiplication of Speed and Mass, which results in a Momentum scalar.
final Energy	multiply(Momentum v)	Calculate the multiplication of Speed and Momentum, which results in a Energy scalar.
static Speed	of(double value, String unitString)	Returns a Speed based on a value and the textual representation of the unit, which can be localized.
static Speed	ofSi(double si)	Return a Speed instance based on an SI value.
SIUnit	siUnit()	Return the SI unit of this quantity.
static Speed	valueOf(String text)	Returns a Speed representation of a textual representation of a value with a unit.

Methods inherited from class org.djunits.quantity.def.Quantity

abs, add, as, compareTo, divide, doubleValue, eq, eq0, equals, floatValue, format, format, ge, ge0, getDisplayUnit, getInUnit, getInUnit, getName, gt, gt0, hashCode, instantiate, interpolate, intValue, isRelative, le, le0, longValue, lt, lt0, max, mean, min, multiply, ne, ne0, negate, of, product, reciprocal, scaleBy, setDisplayUnit, si, subtract, sum, toDisplayString, toDisplayString, toString, toString, toString, toString, toStringSIPrefixed, toStringSIPrefixed, toTextualString, toTextualString, valueOf

Methods inherited from class java.lang.Number

byteValue, shortValue

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.djunits.value.Scalable

divideBy

Methods inherited from interface org.djunits.value.Value

isAbsolute, setDisplayUnit

Field Details

ZERO

public static final Speed ZERO

Constant with value zero.

ONE

public static final Speed ONE

Constant with value one.

NaN

public static final Speed NaN

Constant with value NaN.

POSITIVE_INFINITY

public static final Speed POSITIVE_INFINITY

Constant with value POSITIVE_INFINITY.

NEGATIVE_INFINITY

public static final Speed NEGATIVE_INFINITY

Constant with value NEGATIVE_INFINITY.

POS_MAXVALUE

public static final Speed POS_MAXVALUE

Constant with value MAX_VALUE.

NEG_MAXVALUE

public static final Speed NEG_MAXVALUE

Constant with value -MAX_VALUE.

Constructor Details

Speed

public Speed(double value,
 Speed.Unit unit)

Instantiate a Speed quantity with a unit.

Parameters:

value - the value, expressed in the unit

unit - the unit in which the value is expressed

Speed

public Speed(double value,
 String abbreviation)

Instantiate a Speed quantity with a unit, expressed as a String.

Parameters:

value - the value, expressed in the unit

abbreviation - the String abbreviation of the unit in which the value is expressed

Speed

public Speed(Speed value)

Construct Speed quantity.

Parameters:

value - Scalar from which to construct this instance

Method Details

ofSi

public static Speed ofSi(double si)

Return a Speed instance based on an SI value.

Parameters:

si - the si value

Returns:

the Speed instance based on an SI value

instantiate

public Speed instantiate(double si)

Description copied from class: Quantity

Instantiate a quantity with an SI or base value.

Specified by:

instantiate in class Quantity<Speed,Speed.Unit>

Parameters:

si - the value expressed in the base (SI) unit

Returns:

a quantity with the given SI-value and base (SI) unit

siUnit

public SIUnit siUnit()

Description copied from class: Quantity

Return the SI unit of this quantity.

Overrides:

siUnit in class Quantity<Speed,Speed.Unit>

Returns:

the SI unit of this quantity

valueOf

public static Speed valueOf(String text)

Returns a Speed representation of a textual representation of a value with a unit. The String representation that can be parsed is the double value in the unit, followed by a localized or English abbreviation of the unit. Spaces are allowed, but not required, between the value and the unit.

Parameters:

text - the textual representation to parse into a Speed

Returns:

the Scalar representation of the value in its unit

Throws:

IllegalArgumentException - when the text cannot be parsed

NullPointerException - when the text argument is null

of

public static Speed of(double value,
 String unitString)

Returns a Speed based on a value and the textual representation of the unit, which can be localized.

Parameters:

value - the value to use

unitString - the textual representation of the unit

Returns:

the Scalar representation of the value in its unit

Throws:

IllegalArgumentException - when the unit cannot be parsed or is incorrect

NullPointerException - when the unitString argument is null

divide

public final Dimensionless divide(Speed v)

Calculate the division of Speed and Speed, which results in a Dimensionless scalar.

Parameters:

v - scalar

Returns:

scalar as a division of Speed and Speed

multiply

public final FlowVolume multiply(Area v)

Calculate the multiplication of Speed and Area, which results in a FlowVolume scalar.

Parameters:

v - scalar

Returns:

scalar as a multiplication of Speed and Area

multiply

public final Power multiply(Force v)

Calculate the multiplication of Speed and Force, which results in a Power scalar.

Parameters:

v - scalar

Returns:

scalar as a multiplication of Speed and Force

multiply

public final Acceleration multiply(Frequency v)

Calculate the multiplication of Speed and Frequency, which results in a Acceleration scalar.

Parameters:

v - scalar

Returns:

scalar as a multiplication of Speed and Frequency

divide

public final Frequency divide(Length v)

Calculate the division of Speed and Length, which results in a Frequency scalar.

Parameters:

v - scalar

Returns:

scalar as a division of Speed and Length

divide

public final Length divide(Frequency v)

Calculate the division of Speed and Frequency, which results in a Length scalar.

Parameters:

v - scalar

Returns:

scalar as a division of Speed and Frequency

multiply

public final Frequency multiply(LinearObjectDensity v)

Calculate the multiplication of Speed and LinearObjectDensity, which results in a Frequency scalar.

Parameters:

v - scalar

Returns:

scalar as a multiplication of Speed and LinearObjectDensity

multiply

public final Length multiply(Duration v)

Calculate the multiplication of Speed and Duration, which results in a Length scalar.

Parameters:

v - scalar

Returns:

scalar as a multiplication of Speed and Duration

divide

public final Acceleration divide(Duration v)

Calculate the division of Speed and Duration, which results in a Acceleration scalar.

Parameters:

v - scalar

Returns:

scalar as a division of Speed and Duration

divide

public final Duration divide(Acceleration v)

Calculate the division of Speed and Acceleration, which results in a Duration scalar.

Parameters:

v - scalar

Returns:

scalar as a division of Speed and Acceleration

multiply

public final Force multiply(FlowMass v)

Calculate the multiplication of Speed and FlowMass, which results in a Force scalar.

Parameters:

v - scalar

Returns:

scalar as a multiplication of Speed and FlowMass

multiply

public final Momentum multiply(Mass v)

Calculate the multiplication of Speed and Mass, which results in a Momentum scalar.

Parameters:

v - scalar

Returns:

scalar as a multiplication of Speed and Mass

multiply

public final Energy multiply(Momentum v)

Calculate the multiplication of Speed and Momentum, which results in a Energy scalar.

Parameters:

v - scalar

Returns:

scalar as a multiplication of Speed and Momentum