Package org.djunits.quantity

Class Length

java.lang.Object
java.lang.Number
org.djunits.quantity.def.Quantity<Length>
org.djunits.quantity.Length
All Implemented Interfaces:
Serializable, Comparable<Length>, Additive<Length>, Scalable<Length>, Value<Length>
public class Length extends Quantity<Length>
Length is the measure of distance between two points, expressed in meters (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:

  • Field Details

    • ZERO

      public static final Length ZERO
      Constant with value zero.

    • ONE

      public static final Length ONE
      Constant with value one.

    • NaN

      public static final Length NaN
      Constant with value NaN.

    • POSITIVE_INFINITY

      public static final Length POSITIVE_INFINITY
      Constant with value POSITIVE_INFINITY.

    • NEGATIVE_INFINITY

      public static final Length NEGATIVE_INFINITY
      Constant with value NEGATIVE_INFINITY.

    • POS_MAXVALUE

      public static final Length POS_MAXVALUE
      Constant with value MAX_VALUE.

    • NEG_MAXVALUE

      public static final Length NEG_MAXVALUE
      Constant with value -MAX_VALUE.

  • Constructor Details

    • Length

      public Length(double value, Length.Unit displayUnit, boolean useSi)
      Instantiate a Length quantity with an SI or base value and a display unit.
      Parameters:
      value - the quantity value expressed in the SI or base unit
      displayUnit - the display unit to use
      useSi - use SI value when true, use value in unit when false

    • Length

      public Length(double valueInUnit, Length.Unit unit)
      Instantiate a Length quantity expressed in the given unit.
      Parameters:
      valueInUnit - the quantity value expressed in the given unit
      unit - the unit of the value, also acts as the display unit

  • Method Details

    • ofSi

      public static Length ofSi(double si)
      Return a Length instance based on an SI value.
      Parameters:
      si - the si value
      Returns:
      the Length instance based on an SI value

    • ofSi

      public static Length ofSi(double siValue, Length.Unit displayUnit)
      Instantiate a Length quantity with an SI or base value and a display unit.
      Parameters:
      siValue - the quantity value expressed in the SI or base unit
      displayUnit - the display unit to use
      Returns:
      the Length instance based on an SI value with the given display unit

    • instantiateSi

      public Length instantiateSi(double siValue, UnitInterface<Length> displayUnit)
      Description copied from class: Quantity
      Instantiate a quantity with an SI or base value, and a display unit.
      Specified by:
      instantiateSi in class Quantity<Length>
      Parameters:
      siValue - the value expressed in the base (SI) unit
      displayUnit - the display unit to use for the quantity
      Returns:
      a quantity with the given SI or base value, and the given display unit

    • valueOf

      public static Length valueOf(String text)
      Returns a Length 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 Length
      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 Length of(double valueInUnit, Length.Unit unit)
      Returns a Length based on a value expressed in the unit.
      Parameters:
      valueInUnit - the value, expressed in the given unit
      unit - the unit of the value, also acts as the display unit
      Returns:
      ab Length representation of the value in its unit

    • of

      public static Length of(double valueInUnit, String unitString)
      Returns a Length based on a value and the textual representation of the unit, which can be localized.
      Parameters:
      valueInUnit - the value, expressed in the unit as given by unitString
      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

    • getDisplayUnit

      public Length.Unit getDisplayUnit()
      Description copied from interface: Value
      Retrieve the unit of this Value.
      Specified by:
      getDisplayUnit in interface Value<Length>
      Overrides:
      getDisplayUnit in class Quantity<Length>
      Returns:
      the unit of this Value

    • add

      public Position add(Position position)
      Add an (absolute) position to this length, and return a position. The unit of the return value will be the unit of this length, and the reference of the return value will be the reference belonging to the given position. R.add(A) = unit of R and reference value of A.
      Parameters:
      position - the absolute position to add
      Returns:
      the absolute position plus this length

    • divide

      public Dimensionless divide(Length v)
      Calculate the division of Length and Length, which results in a Dimensionless quantity.
      Parameters:
      v - quantity
      Returns:
      quantity as a division of Length and Length

    • multiply

      public Dimensionless multiply(LinearObjectDensity v)
      Calculate the multiplication of Length and LinearObjectDensity, which results in a Dimensionless quantity.
      Parameters:
      v - quantity
      Returns:
      quantity as a multiplication of Length and LinearObjectDensity

    • multiply

      public Area multiply(Length v)
      Calculate the multiplication of Length and Length, which results in a Area quantity.
      Parameters:
      v - quantity
      Returns:
      quantity as a multiplication of Length and Length

    • divide

      public Area divide(LinearObjectDensity v)
      Calculate the division of Length and LinearObjectDensity, which results in a Area quantity.
      Parameters:
      v - quantity
      Returns:
      quantity as a division of Length and LinearObjectDensity

    • divide

      public LinearObjectDensity divide(Area v)
      Calculate the division of Length and Area, which results in a LinearObjectDensity quantity.
      Parameters:
      v - quantity
      Returns:
      quantity as a division of Length and Area

    • multiply

      public Volume multiply(Area v)
      Calculate the multiplication of Length and Area, which results in a Volume quantity.
      Parameters:
      v - quantity
      Returns:
      quantity as a multiplication of Length and Area

    • multiply

      public Energy multiply(Force v)
      Calculate the multiplication of Length and Force, which results in a Energy quantity.
      Parameters:
      v - quantity
      Returns:
      quantity as a multiplication of Length and Force

    • multiply

      public Speed multiply(Frequency v)
      Calculate the multiplication of Length and Frequency, which results in a Speed quantity.
      Parameters:
      v - quantity
      Returns:
      quantity as a multiplication of Length and Frequency

    • divide

      public Speed divide(Duration v)
      Calculate the division of Length and Duration, which results in a Speed quantity.
      Parameters:
      v - quantity
      Returns:
      quantity as a division of Length and Duration

    • divide

      public Duration divide(Speed v)
      Calculate the division of Length and Speed, which results in a Duration quantity.
      Parameters:
      v - quantity
      Returns:
      quantity as a division of Length and Speed

    • multiply

      public Momentum multiply(FlowMass v)
      Calculate the multiplication of Length and FlowMass, which results in a Momentum quantity.
      Parameters:
      v - quantity
      Returns:
      quantity as a multiplication of Length and FlowMass

    • reciprocal

      public LinearObjectDensity reciprocal()
      Description copied from class: Quantity
      Return the reciprocal of this quantity (1/q).
      Overrides:
      reciprocal in class Quantity<Length>
      Returns:
      the reciprocal of this quantity, with the correct SI units