1 package org.djunits.quantity;
2
3 import org.djunits.quantity.def.Quantity;
4 import org.djunits.unit.AbstractUnit;
5 import org.djunits.unit.UnitRuntimeException;
6 import org.djunits.unit.Unitless;
7 import org.djunits.unit.Units;
8 import org.djunits.unit.scale.LinearScale;
9 import org.djunits.unit.scale.Scale;
10 import org.djunits.unit.si.SIUnit;
11 import org.djunits.unit.system.UnitSystem;
12
13 /**
14 * Power is the rate of energy transfer or work done per unit time, measured in watts (W).
15 * <p>
16 * Copyright (c) 2025-2026 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved. See
17 * for project information <a href="https://djunits.org" target="_blank">https://djunits.org</a>. The DJUNITS project is
18 * distributed under a <a href="https://djunits.org/docs/license.html" target="_blank">three-clause BSD-style license</a>.
19 * @author Alexander Verbraeck
20 */
21 public class Power extends Quantity<Power, Power.Unit>
22 {
23 /** Constant with value zero. */
24 public static final Power ZERO = Power.ofSi(0.0);
25
26 /** Constant with value one. */
27 public static final Power ONE = Power.ofSi(1.0);
28
29 /** Constant with value NaN. */
30 @SuppressWarnings("checkstyle:constantname")
31 public static final Power NaN = Power.ofSi(Double.NaN);
32
33 /** Constant with value POSITIVE_INFINITY. */
34 public static final Power POSITIVE_INFINITY = Power.ofSi(Double.POSITIVE_INFINITY);
35
36 /** Constant with value NEGATIVE_INFINITY. */
37 public static final Power NEGATIVE_INFINITY = Power.ofSi(Double.NEGATIVE_INFINITY);
38
39 /** Constant with value MAX_VALUE. */
40 public static final Power POS_MAXVALUE = Power.ofSi(Double.MAX_VALUE);
41
42 /** Constant with value -MAX_VALUE. */
43 public static final Power NEG_MAXVALUE = Power.ofSi(-Double.MAX_VALUE);
44
45 /** */
46 private static final long serialVersionUID = 600L;
47
48 /**
49 * Instantiate a Power quantity with a unit.
50 * @param value the value, expressed in the unit
51 * @param unit the unit in which the value is expressed
52 */
53 public Power(final double value, final Power.Unit unit)
54 {
55 super(value, unit);
56 }
57
58 /**
59 * Instantiate a Power quantity with a unit, expressed as a String.
60 * @param value the value, expressed in the unit
61 * @param abbreviation the String abbreviation of the unit in which the value is expressed
62 */
63 public Power(final double value, final String abbreviation)
64 {
65 this(value, Units.resolve(Power.Unit.class, abbreviation));
66 }
67
68 /**
69 * Construct Power quantity.
70 * @param value Scalar from which to construct this instance
71 */
72 public Power(final Power value)
73 {
74 super(value.si(), Power.Unit.SI);
75 setDisplayUnit(value.getDisplayUnit());
76 }
77
78 /**
79 * Return a Power instance based on an SI value.
80 * @param si the si value
81 * @return the Power instance based on an SI value
82 */
83 public static Power ofSi(final double si)
84 {
85 return new Power(si, Power.Unit.SI);
86 }
87
88 @Override
89 public Power instantiate(final double si)
90 {
91 return ofSi(si);
92 }
93
94 @Override
95 public SIUnit siUnit()
96 {
97 return Power.Unit.SI_UNIT;
98 }
99
100 /**
101 * Returns a Power representation of a textual representation of a value with a unit. The String representation that can be
102 * parsed is the double value in the unit, followed by a localized or English abbreviation of the unit. Spaces are allowed,
103 * but not required, between the value and the unit.
104 * @param text the textual representation to parse into a Power
105 * @return the Scalar representation of the value in its unit
106 * @throws IllegalArgumentException when the text cannot be parsed
107 * @throws NullPointerException when the text argument is null
108 */
109 public static Power valueOf(final String text)
110 {
111 return Quantity.valueOf(text, ZERO);
112 }
113
114 /**
115 * Returns a Power based on a value and the textual representation of the unit, which can be localized.
116 * @param value the value to use
117 * @param unitString the textual representation of the unit
118 * @return the Scalar representation of the value in its unit
119 * @throws IllegalArgumentException when the unit cannot be parsed or is incorrect
120 * @throws NullPointerException when the unitString argument is null
121 */
122 public static Power of(final double value, final String unitString)
123 {
124 return Quantity.of(value, unitString, ZERO);
125 }
126
127 /**
128 * Calculate the division of Power and Power, which results in a Dimensionless quantity.
129 * @param v quantity
130 * @return quantity as a division of Power and Power
131 */
132 public final Dimensionless divide(final Power v)
133 {
134 return new Dimensionless(this.si() / v.si(), Unitless.BASE);
135 }
136
137 /**
138 * Calculate the multiplication of Power and Duration, which results in a Energy scalar.
139 * @param v scalar
140 * @return scalar as a multiplication of Power and Duration
141 */
142 public final Energy multiply(final Duration v)
143 {
144 return new Energy(this.si() * v.si(), Energy.Unit.SI);
145 }
146
147 /**
148 * Calculate the division of Power and Frequency, which results in a Energy scalar.
149 * @param v scalar
150 * @return scalar as a division of Power and Frequency
151 */
152 public final Energy divide(final Frequency v)
153 {
154 return new Energy(this.si() / v.si(), Energy.Unit.SI);
155 }
156
157 /**
158 * Calculate the division of Power and Energy, which results in a Frequency scalar.
159 * @param v scalar
160 * @return scalar as a division of Power and Energy
161 */
162 public final Frequency divide(final Energy v)
163 {
164 return new Frequency(this.si() / v.si(), Frequency.Unit.SI);
165 }
166
167 /**
168 * Calculate the division of Power and Speed, which results in a Force scalar.
169 * @param v scalar
170 * @return scalar as a division of Power and Speed
171 */
172 public final Force divide(final Speed v)
173 {
174 return new Force(this.si() / v.si(), Force.Unit.SI);
175 }
176
177 /**
178 * Calculate the division of Power and Force, which results in a Speed scalar.
179 * @param v scalar
180 * @return scalar as a division of Power and Force
181 */
182 public final Speed divide(final Force v)
183 {
184 return new Speed(this.si() / v.si(), Speed.Unit.SI);
185 }
186
187 /**
188 * Calculate the division of Power and ElectricPotential, which results in a ElectricCurrent scalar.
189 * @param v scalar
190 * @return scalar as a division of Power and ElectricPotential
191 */
192 public final ElectricCurrent divide(final ElectricPotential v)
193 {
194 return new ElectricCurrent(this.si() / v.si(), ElectricCurrent.Unit.SI);
195 }
196
197 /**
198 * Calculate the division of Power and ElectricCurrent, which results in a ElectricPotential scalar.
199 * @param v scalar
200 * @return scalar as a division of Power and ElectricCurrent
201 */
202 public final ElectricPotential divide(final ElectricCurrent v)
203 {
204 return new ElectricPotential(this.si() / v.si(), ElectricPotential.Unit.SI);
205 }
206
207 /**
208 * Calculate the division of Power and Acceleration, which results in a Momentum scalar.
209 * @param v scalar
210 * @return scalar as a division of Power and Acceleration
211 */
212 public final Momentum divide(final Acceleration v)
213 {
214 return new Momentum(this.si() / v.si(), Momentum.Unit.SI);
215 }
216
217 /**
218 * Calculate the division of Power and Momentum, which results in a Acceleration scalar.
219 * @param v scalar
220 * @return scalar as a division of Power and Momentum
221 */
222 public final Acceleration divide(final Momentum v)
223 {
224 return new Acceleration(this.si() / v.si(), Acceleration.Unit.SI);
225 }
226
227 /******************************************************************************************************/
228 /********************************************** UNIT CLASS ********************************************/
229 /******************************************************************************************************/
230
231 /**
232 * Power.Unit encodes the units for the rate of energy transfer or work done per unit time.
233 * <p>
234 * Copyright (c) 2025-2026 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved.
235 * See for project information <a href="https://djunits.org" target="_blank">https://djunits.org</a>. The DJUNITS project is
236 * distributed under a <a href="https://djunits.org/docs/license.html" target="_blank">three-clause BSD-style license</a>.
237 * @author Alexander Verbraeck
238 */
239 @SuppressWarnings("checkstyle:constantname")
240 public static class Unit extends AbstractUnit<Power.Unit, Power>
241 {
242 /** The dimensions of power: kgm2/s3. */
243 public static final SIUnit SI_UNIT = SIUnit.of("kgm2/s3");
244
245 /** Watt. */
246 public static final Power.Unit W = new Power.Unit("W", "watt", 1.0, UnitSystem.SI_DERIVED);
247
248 /** The SI or BASE unit. */
249 public static final Power.Unit SI = W.generateSiPrefixes(false, false);
250
251 /** microwatt. */
252 public static final Power.Unit muW = Units.resolve(Power.Unit.class, "muW");
253
254 /** milliwatt. */
255 public static final Power.Unit mW = Units.resolve(Power.Unit.class, "mW");
256
257 /** kilowatt. */
258 public static final Power.Unit kW = Units.resolve(Power.Unit.class, "kW");
259
260 /** megawatt. */
261 public static final Power.Unit MW = Units.resolve(Power.Unit.class, "MW");
262
263 /** gigawatt. */
264 public static final Power.Unit GW = Units.resolve(Power.Unit.class, "GW");
265
266 /** terawatt. */
267 public static final Power.Unit TW = Units.resolve(Power.Unit.class, "TW");
268
269 /** petawatt. */
270 public static final Power.Unit PW = Units.resolve(Power.Unit.class, "PW");
271
272 /** foot-pound-force per hour. */
273 public static final Power.Unit ft_lbf_h = SI.deriveUnit("ft.lbf/h", "foot pound-force per hour",
274 Length.Unit.CONST_FT * Mass.Unit.CONST_LB * Acceleration.Unit.CONST_GRAVITY / 3600.0, UnitSystem.IMPERIAL);
275
276 /** foot-pound-force per minute. */
277 public static final Power.Unit ft_lbf_min = SI.deriveUnit("ft.lbf/min", "foot pound-force per minute",
278 Length.Unit.CONST_FT * Mass.Unit.CONST_LB * Acceleration.Unit.CONST_GRAVITY / 60.0, UnitSystem.IMPERIAL);
279
280 /** foot-pound-force per second. */
281 public static final Power.Unit ft_lbf_s = SI.deriveUnit("ft.lbf/s", "foot pound-force per second",
282 Length.Unit.CONST_FT * Mass.Unit.CONST_LB * Acceleration.Unit.CONST_GRAVITY, UnitSystem.IMPERIAL);
283
284 /** horsepower (metric). */
285 public static final Power.Unit hp_M = W.deriveUnit("hp(M)", "horsepower (metric)", 735.49875, UnitSystem.OTHER);
286
287 /** sthene-meter per second. */
288 public static final Power.Unit sn_m_s = SI.deriveUnit("sn.m/s", "sthene meter per second", 1000.0, UnitSystem.MTS);
289
290 /** erg per second. */
291 public static final Power.Unit erg_s = SI.deriveUnit("erg/s", "erg per second", 1.0E-7, UnitSystem.CGS);
292
293 /**
294 * Create a new Power unit.
295 * @param id the id or main abbreviation of the unit
296 * @param name the full name of the unit
297 * @param scaleFactorToBaseUnit the scale factor of the unit to convert it TO the base (SI) unit
298 * @param unitSystem the unit system such as SI or IMPERIAL
299 */
300 public Unit(final String id, final String name, final double scaleFactorToBaseUnit, final UnitSystem unitSystem)
301 {
302 super(id, name, new LinearScale(scaleFactorToBaseUnit), unitSystem);
303 }
304
305 /**
306 * Return a derived unit for this unit, with textual abbreviation(s) and a display abbreviation.
307 * @param textualAbbreviation the textual abbreviation of the unit, which doubles as the id
308 * @param displayAbbreviation the display abbreviation of the unit
309 * @param name the full name of the unit
310 * @param scale the scale to use to convert between this unit and the standard (e.g., SI, BASE) unit
311 * @param unitSystem unit system, e.g. SI or Imperial
312 */
313 public Unit(final String textualAbbreviation, final String displayAbbreviation, final String name, final Scale scale,
314 final UnitSystem unitSystem)
315 {
316 super(textualAbbreviation, displayAbbreviation, name, scale, unitSystem);
317 }
318
319 @Override
320 public SIUnit siUnit()
321 {
322 return SI_UNIT;
323 }
324
325 @Override
326 public Unit getBaseUnit()
327 {
328 return SI;
329 }
330
331 @Override
332 public Power ofSi(final double si)
333 {
334 return Power.ofSi(si);
335 }
336
337 @Override
338 public Unit deriveUnit(final String textualAbbreviation, final String displayAbbreviation, final String name,
339 final double scaleFactor, final UnitSystem unitSystem)
340 {
341 if (getScale() instanceof LinearScale ls)
342 {
343 return new Power.Unit(textualAbbreviation, displayAbbreviation, name,
344 new LinearScale(ls.getScaleFactorToBaseUnit() * scaleFactor), unitSystem);
345 }
346 throw new UnitRuntimeException("Only possible to derive a unit from a unit with a linear scale");
347 }
348
349 }
350 }