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