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1   package org.djunits.quantity;
2   
3   import org.djunits.quantity.def.Quantity;
4   import org.djunits.unit.AbstractUnit;
5   import org.djunits.unit.UnitInterface;
6   import org.djunits.unit.UnitRuntimeException;
7   import org.djunits.unit.Unitless;
8   import org.djunits.unit.scale.LinearScale;
9   import org.djunits.unit.scale.Scale;
10  import org.djunits.unit.si.SIPrefix;
11  import org.djunits.unit.si.SIUnit;
12  import org.djunits.unit.system.UnitSystem;
13  
14  /**
15   * Angular velocity is the rate of rotation around an axis, measured in radians per second (rad/s).
16   * <p>
17   * Copyright (c) 2025-2026 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved. See
18   * for project information <a href="https://djunits.org" target="_blank">https://djunits.org</a>. The DJUNITS project is
19   * distributed under a <a href="https://djunits.org/docs/license.html" target="_blank">three-clause BSD-style license</a>.
20   * @author Alexander Verbraeck
21   */
22  public class AngularVelocity extends Quantity<AngularVelocity>
23  {
24      /** Constant with value zero. */
25      public static final AngularVelocity ZERO = ofSi(0.0);
26  
27      /** Constant with value one. */
28      public static final AngularVelocity ONE = ofSi(1.0);
29  
30      /** Constant with value NaN. */
31      @SuppressWarnings("checkstyle:constantname")
32      public static final AngularVelocity NaN = ofSi(Double.NaN);
33  
34      /** Constant with value POSITIVE_INFINITY. */
35      public static final AngularVelocity POSITIVE_INFINITY = ofSi(Double.POSITIVE_INFINITY);
36  
37      /** Constant with value NEGATIVE_INFINITY. */
38      public static final AngularVelocity NEGATIVE_INFINITY = ofSi(Double.NEGATIVE_INFINITY);
39  
40      /** Constant with value MAX_VALUE. */
41      public static final AngularVelocity POS_MAXVALUE = ofSi(Double.MAX_VALUE);
42  
43      /** Constant with value -MAX_VALUE. */
44      public static final AngularVelocity NEG_MAXVALUE = ofSi(-Double.MAX_VALUE);
45  
46      /** */
47      private static final long serialVersionUID = 600L;
48  
49      /**
50       * Instantiate a AngularVelocity quantity with an SI or base value and a display unit.
51       * @param value the quantity value expressed in the SI or base unit
52       * @param displayUnit the display unit to use
53       * @param useSi use SI value when true, use value in unit when false
54       */
55      public AngularVelocity(final double value, final AngularVelocity.Unit displayUnit, final boolean useSi)
56      {
57          super(value, displayUnit, useSi);
58      }
59  
60      /**
61       * Instantiate a AngularVelocity quantity expressed in the given unit.
62       * @param valueInUnit the quantity value expressed in the given unit
63       * @param unit the unit of the value, also acts as the display unit
64       */
65      public AngularVelocity(final double valueInUnit, final AngularVelocity.Unit unit)
66      {
67          this(valueInUnit, unit, false);
68      }
69  
70      /**
71       * Return a AngularVelocity instance based on an SI value.
72       * @param si the si value
73       * @return the AngularVelocity instance based on an SI value
74       */
75      public static AngularVelocity ofSi(final double si)
76      {
77          return new AngularVelocity(si, AngularVelocity.Unit.SI, true);
78      }
79  
80      /**
81       * Instantiate a AngularVelocity quantity with an SI or base value and a display unit.
82       * @param siValue the quantity value expressed in the SI or base unit
83       * @param displayUnit the display unit to use
84       * @return the AngularVelocity instance based on an SI value with the given display unit
85       */
86      public static AngularVelocity ofSi(final double siValue, final AngularVelocity.Unit displayUnit)
87      {
88          return new AngularVelocity(siValue, displayUnit, true);
89      }
90  
91      @Override
92      public AngularVelocity instantiateSi(final double siValue, final UnitInterface<AngularVelocity> displayUnit)
93      {
94          return new AngularVelocity(siValue, (AngularVelocity.Unit) displayUnit, true);
95      }
96  
97      /**
98       * Returns a AngularVelocity representation of a textual representation of a value with a unit. The String representation
99       * that can be parsed is the double value in the unit, followed by a localized or English abbreviation of the unit. Spaces
100      * are allowed, but not required, between the value and the unit.
101      * @param text the textual representation to parse into a AngularVelocity
102      * @return the Scalar representation of the value in its unit
103      * @throws IllegalArgumentException when the text cannot be parsed
104      * @throws NullPointerException when the text argument is null
105      */
106     public static AngularVelocity valueOf(final String text)
107     {
108         return Quantity.valueOf(text, ZERO);
109     }
110 
111     /**
112      * Returns a AngularVelocity based on a value expressed in the unit.
113      * @param valueInUnit the value, expressed in the given unit
114      * @param unit the unit of the value, also acts as the display unit
115      * @return ab AngularVelocity representation of the value in its unit
116      */
117     public static AngularVelocity of(final double valueInUnit, final AngularVelocity.Unit unit)
118     {
119         return new AngularVelocity(valueInUnit, unit);
120     }
121 
122     /**
123      * Returns a AngularVelocity based on a value and the textual representation of the unit, which can be localized.
124      * @param valueInUnit the value, expressed in the unit as given by unitString
125      * @param unitString the textual representation of the unit
126      * @return the Scalar representation of the value in its unit
127      * @throws IllegalArgumentException when the unit cannot be parsed or is incorrect
128      * @throws NullPointerException when the unitString argument is null
129      */
130     public static AngularVelocity of(final double valueInUnit, final String unitString)
131     {
132         return Quantity.of(valueInUnit, unitString, ZERO);
133     }
134 
135     @Override
136     public AngularVelocity.Unit getDisplayUnit()
137     {
138         return (AngularVelocity.Unit) super.getDisplayUnit();
139     }
140 
141     /**
142      * Calculate the division of AngularVelocity and AngularVelocity, which results in a Dimensionless scalar.
143      * @param v scalar
144      * @return scalar as a division of AngularVelocity and AngularVelocity
145      */
146     public Dimensionless divide(final AngularVelocity v)
147     {
148         return new Dimensionless(this.si() / v.si(), Unitless.BASE);
149     }
150 
151     /******************************************************************************************************/
152     /********************************************** UNIT CLASS ********************************************/
153     /******************************************************************************************************/
154 
155     /**
156      * AngularVelocity.Unit encodes the units of angle (radians, degrees).
157      * <p>
158      * Copyright (c) 2025-2026 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved.
159      * See for project information <a href="https://djunits.org" target="_blank">https://djunits.org</a>. The DJUNITS project is
160      * distributed under a <a href="https://djunits.org/docs/license.html" target="_blank">three-clause BSD-style license</a>.
161      * @author Alexander Verbraeck
162      */
163     @SuppressWarnings("checkstyle:constantname")
164     public static class Unit extends AbstractUnit<AngularVelocity>
165     {
166         /** The dimensions of AngularVelocity: rad/s. */
167         public static final SIUnit SI_UNIT = SIUnit.of("rad/s");
168 
169         /** radian per second. */
170         public static final AngularVelocity.Unit rad_s =
171                 new AngularVelocity.Unit("rad/s", "radians per second", 1.0, UnitSystem.SI_DERIVED);
172 
173         /** The SI or BASE unit. */
174         public static final AngularVelocity.Unit SI = rad_s;
175 
176         /** degree per second. */
177         public static final AngularVelocity.Unit deg_s =
178                 rad_s.deriveUnit("deg/s", "\u00b0/s", "degree per second", Math.PI / 180.0, UnitSystem.SI_ACCEPTED, null);
179 
180         /** arcminute per second. */
181         public static final AngularVelocity.Unit arcmin_s =
182                 deg_s.deriveUnit("arcmin/s", "'/s", "arcminute per second", 1.0 / 60.0, UnitSystem.OTHER, null);
183 
184         /** arcsecond per second. */
185         public static final AngularVelocity.Unit arcsec_s =
186                 deg_s.deriveUnit("arcsec/s", "\"/s", "arcsecond per second", 1.0 / 3600.0, UnitSystem.OTHER, null);
187 
188         /** grad per second. */
189         public static final AngularVelocity.Unit grad_s =
190                 rad_s.deriveUnit("grad/s", "grad/s", "gradian per second", 2.0 * Math.PI / 400.0, UnitSystem.OTHER, null);
191 
192         /** centesimal arcminute per second. */
193         public static final AngularVelocity.Unit cdm_s =
194                 grad_s.deriveUnit("cdm/s", "c'/s", "centesimal arcminute per second", 1.0 / 100.0, UnitSystem.OTHER, null);
195 
196         /** centesimal arcsecond per second. */
197         public static final AngularVelocity.Unit cds_s =
198                 grad_s.deriveUnit("cds/s", "c\"/s", "centesimal arcsecond per second", 1.0 / 10000.0, UnitSystem.OTHER, null);
199 
200         /**
201          * Create a new AngularVelocity unit.
202          * @param id the id or main abbreviation of the unit
203          * @param name the full name of the unit
204          * @param scaleFactorToBaseUnit the scale factor of the unit to convert it TO the base (SI) unit
205          * @param unitSystem the unit system such as SI or IMPERIAL
206          */
207         public Unit(final String id, final String name, final double scaleFactorToBaseUnit, final UnitSystem unitSystem)
208         {
209             super(id, name, scaleFactorToBaseUnit, unitSystem);
210         }
211 
212         /**
213          * Return a derived unit for this unit, with textual abbreviation(s) and a display abbreviation.
214          * @param textualAbbreviation the textual abbreviation of the unit, which doubles as the id
215          * @param displayAbbreviation the display abbreviation of the unit
216          * @param name the full name of the unit
217          * @param scale the scale to use to convert from this unit to the standard (e.g., SI, BASE) unit
218          * @param unitSystem unit system, e.g. SI or Imperial
219          * @param siPrefix the SI Prefix of this unit
220          */
221         public Unit(final String textualAbbreviation, final String displayAbbreviation, final String name, final Scale scale,
222                 final UnitSystem unitSystem, final SIPrefix siPrefix)
223         {
224             super(textualAbbreviation, displayAbbreviation, name, scale, unitSystem, siPrefix);
225         }
226 
227         @Override
228         public SIUnit siUnit()
229         {
230             return SI_UNIT;
231         }
232 
233         @Override
234         public Unit getBaseUnit()
235         {
236             return SI;
237         }
238 
239         @Override
240         public AngularVelocity ofSi(final double si, final UnitInterface<AngularVelocity> displayUnit)
241         {
242             return new AngularVelocity(si, (Unit) displayUnit, true);
243         }
244 
245         @Override
246         public AngularVelocity.Unit deriveUnit(final String textualAbbreviation, final String displayAbbreviation,
247                 final String name, final double scaleFactor, final UnitSystem unitSystem, final SIPrefix siPrefix)
248         {
249             if (getScale() instanceof LinearScale ls)
250             {
251                 return new AngularVelocity.Unit(textualAbbreviation, displayAbbreviation, name,
252                         new LinearScale(ls.getScaleFactorToBaseUnit() * scaleFactor), unitSystem, siPrefix);
253             }
254             throw new UnitRuntimeException("Only possible to derive a unit from a unit with a linear scale");
255         }
256 
257     }
258 
259 }