Package org.djunits.quantity

Class LinearDensity

java.lang.Object

java.lang.Number

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

org.djunits.quantity.LinearDensity

All Implemented Interfaces:

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

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

Linear density is mass per unit length of an object, measured in kilograms per meter (kg/m).

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	LinearDensity.Unit	LinearDensity.Unit encodes unit for mass per unit length.

Field Summary

Fields

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

Constructor Summary

Constructors

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

Method Summary

Modifier and Type	Method	Description
final Dimensionless	divide(LinearDensity v)	Calculate the division of LinearDensity and LinearDensity, which results in a Dimensionless quantity.
final Mass	divide(LinearObjectDensity lod)	Divides this linear density by a linear object density to yield a mass.
final LinearObjectDensity	divide(Mass mass)	Divides this linear density by a mass to yield a linear object density.
LinearDensity	instantiate(double si)	Instantiate a quantity with an SI or base value.
final Mass	multiply(Length length)	Multiplies this linear density by a length to yield a mass.
final FlowMass	multiply(Speed speed)	Multiplies this linear density by a speed to yield a mass flow.
static LinearDensity	of(double value, String unitString)	Returns a LinearDensity based on a value and the textual representation of the unit, which can be localized.
static LinearDensity	ofSi(double si)	Return a LinearDensity instance based on an SI value.
SIUnit	siUnit()	Return the SI unit of this quantity.
static LinearDensity	valueOf(String text)	Returns a LinearDensity 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 LinearDensity ZERO

Constant with value zero.

ONE

public static final LinearDensity ONE

Constant with value one.

NaN

public static final LinearDensity NaN

Constant with value NaN.

POSITIVE_INFINITY

public static final LinearDensity POSITIVE_INFINITY

Constant with value POSITIVE_INFINITY.

NEGATIVE_INFINITY

public static final LinearDensity NEGATIVE_INFINITY

Constant with value NEGATIVE_INFINITY.

POS_MAXVALUE

public static final LinearDensity POS_MAXVALUE

Constant with value MAX_VALUE.

NEG_MAXVALUE

public static final LinearDensity NEG_MAXVALUE

Constant with value -MAX_VALUE.

Constructor Details

LinearDensity

public LinearDensity(double value,
 LinearDensity.Unit unit)

Instantiate a LinearDensity quantity with a unit.

Parameters:

value - the value, expressed in the unit

unit - the unit in which the value is expressed

LinearDensity

public LinearDensity(double value,
 String abbreviation)

Instantiate a LinearDensity 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

LinearDensity

public LinearDensity(LinearDensity value)

Construct LinearDensity quantity.

Parameters:

value - Scalar from which to construct this instance

Method Details

ofSi

public static LinearDensity ofSi(double si)

Return a LinearDensity instance based on an SI value.

Parameters:

si - the si value

Returns:

the LinearDensity instance based on an SI value

instantiate

public LinearDensity instantiate(double si)

Description copied from class: Quantity

Instantiate a quantity with an SI or base value.

Specified by:

instantiate in class Quantity<LinearDensity,LinearDensity.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<LinearDensity,LinearDensity.Unit>

Returns:

the SI unit of this quantity

valueOf

public static LinearDensity valueOf(String text)

Returns a LinearDensity 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 LinearDensity

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 LinearDensity of(double value,
 String unitString)

Returns a LinearDensity 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(LinearDensity v)

Calculate the division of LinearDensity and LinearDensity, which results in a Dimensionless quantity.

Parameters:

v - quantity

Returns:

quantity as a division of LinearDensity and LinearDensity

divide

public final LinearObjectDensity divide(Mass mass)

Divides this linear density by a mass to yield a linear object density.

Formula: (kg/m) / kg = 1/m.

Parameters:

mass - the mass divisor; must not be null.

Returns:

the resulting linear object density in SI (1/m).

Throws:

NullPointerException - if mass is null.

divide

public final Mass divide(LinearObjectDensity lod)

Divides this linear density by a linear object density to yield a mass.

Formula: (kg/m) / (1/m) = kg.

Parameters:

lod - the linear object density divisor; must not be null.

Returns:

the resulting mass in SI (kg).

Throws:

NullPointerException - if lod is null.

multiply

public final Mass multiply(Length length)

Multiplies this linear density by a length to yield a mass.

Formula: (kg/m) * m = kg.

Parameters:

length - the length multiplier; must not be null.

Returns:

the resulting mass in SI (kg).

Throws:

NullPointerException - if length is null.

multiply

public final FlowMass multiply(Speed speed)

Multiplies this linear density by a speed to yield a mass flow.

Formula: (kg/m) * (m/s) = kg/s.

Parameters:

speed - the speed multiplier; must not be null.

Returns:

the resulting mass flow in SI (kg/s).

Throws:

NullPointerException - if speed is null.