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 * Torque is a measure of rotational force about an axis, measured in newton meters (Nm).
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 Torque extends Quantity<Torque, Torque.Unit>
22 {
23 /** Constant with value zero. */
24 public static final Torque ZERO = Torque.ofSi(0.0);
25
26 /** Constant with value one. */
27 public static final Torque ONE = Torque.ofSi(1.0);
28
29 /** Constant with value NaN. */
30 @SuppressWarnings("checkstyle:constantname")
31 public static final Torque NaN = Torque.ofSi(Double.NaN);
32
33 /** Constant with value POSITIVE_INFINITY. */
34 public static final Torque POSITIVE_INFINITY = Torque.ofSi(Double.POSITIVE_INFINITY);
35
36 /** Constant with value NEGATIVE_INFINITY. */
37 public static final Torque NEGATIVE_INFINITY = Torque.ofSi(Double.NEGATIVE_INFINITY);
38
39 /** Constant with value MAX_VALUE. */
40 public static final Torque POS_MAXVALUE = Torque.ofSi(Double.MAX_VALUE);
41
42 /** Constant with value -MAX_VALUE. */
43 public static final Torque NEG_MAXVALUE = Torque.ofSi(-Double.MAX_VALUE);
44
45 /** */
46 private static final long serialVersionUID = 600L;
47
48 /**
49 * Instantiate a Torque 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 Torque(final double value, final Torque.Unit unit)
54 {
55 super(value, unit);
56 }
57
58 /**
59 * Instantiate a Torque 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 Torque(final double value, final String abbreviation)
64 {
65 this(value, Units.resolve(Torque.Unit.class, abbreviation));
66 }
67
68 /**
69 * Construct Torque quantity.
70 * @param value Scalar from which to construct this instance
71 */
72 public Torque(final Torque value)
73 {
74 super(value.si(), Torque.Unit.SI);
75 setDisplayUnit(value.getDisplayUnit());
76 }
77
78 /**
79 * Return a Torque instance based on an SI value.
80 * @param si the si value
81 * @return the Torque instance based on an SI value
82 */
83 public static Torque ofSi(final double si)
84 {
85 return new Torque(si, Torque.Unit.SI);
86 }
87
88 @Override
89 public Torque instantiate(final double si)
90 {
91 return ofSi(si);
92 }
93
94 @Override
95 public SIUnit siUnit()
96 {
97 return Torque.Unit.SI_UNIT;
98 }
99
100 /**
101 * Returns a Torque 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 Torque
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 Torque valueOf(final String text)
110 {
111 return Quantity.valueOf(text, ZERO);
112 }
113
114 /**
115 * Returns a Torque 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 Torque of(final double value, final String unitString)
123 {
124 return Quantity.of(value, unitString, ZERO);
125 }
126
127 /**
128 * Calculate the division of Torque and Torque, which results in a Dimensionless quantity.
129 * @param v quantity
130 * @return quantity as a division of Torque and Torque
131 */
132 public final Dimensionless divide(final Torque v)
133 {
134 return new Dimensionless(this.si() / v.si(), Unitless.BASE);
135 }
136
137 /**
138 * Calculate the division of Torque and Force, which results in a Length scalar.
139 * @param v scalar
140 * @return scalar as a division of Torque and Force
141 */
142 public final Length divide(final Force v)
143 {
144 return new Length(this.si() / v.si(), Length.Unit.SI);
145 }
146
147 /**
148 * Calculate the division of Torque and Length, which results in a Force scalar.
149 * @param v scalar
150 * @return scalar as a division of Torque and Length
151 */
152 public final Force divide(final Length v)
153 {
154 return new Force(this.si() / v.si(), Force.Unit.SI);
155 }
156
157 /**
158 * Calculate the multiplication of Torque and LinearObjectDensity, which results in a Force scalar.
159 * @param v scalar
160 * @return scalar as a multiplication of Torque and LinearObjectDensity
161 */
162 public final Force multiply(final LinearObjectDensity v)
163 {
164 return new Force(this.si() * v.si(), Force.Unit.SI);
165 }
166
167 /**
168 * Calculate the division of Torque and Duration, which results in a Power scalar.
169 * @param v scalar
170 * @return scalar as a division of Torque and Duration
171 */
172 public final Power divide(final Duration v)
173 {
174 return new Power(this.si() / v.si(), Power.Unit.SI);
175 }
176
177 /**
178 * Calculate the division of Torque and Power, which results in a Duration scalar.
179 * @param v scalar
180 * @return scalar as a division of Torque and Power
181 */
182 public final Duration divide(final Power v)
183 {
184 return new Duration(this.si() / v.si(), Duration.Unit.SI);
185 }
186
187 /**
188 * Calculate the multiplication of Torque and Frequency, which results in a Power scalar.
189 * @param v scalar
190 * @return scalar as a multiplication of Torque and Frequency
191 */
192 public final Power multiply(final Frequency v)
193 {
194 return new Power(this.si() * v.si(), Power.Unit.SI);
195 }
196
197 /**
198 * Calculate the division of Torque and Volume, which results in a Pressure scalar.
199 * @param v scalar
200 * @return scalar as a division of Torque and Volume
201 */
202 public final Pressure divide(final Volume v)
203 {
204 return new Pressure(this.si() / v.si(), Pressure.Unit.SI);
205 }
206
207 /**
208 * Calculate the division of Torque and Pressure, which results in a Volume scalar.
209 * @param v scalar
210 * @return scalar as a division of Torque and Pressure
211 */
212 public final Volume divide(final Pressure v)
213 {
214 return new Volume(this.si() / v.si(), Volume.Unit.SI);
215 }
216
217 /******************************************************************************************************/
218 /********************************************** UNIT CLASS ********************************************/
219 /******************************************************************************************************/
220
221 /**
222 * Torque.Unit encodes the units of rotational force about an axis, measured in newton meters (Nm).
223 * <p>
224 * Copyright (c) 2025-2026 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved.
225 * See for project information <a href="https://djunits.org" target="_blank">https://djunits.org</a>. The DJUNITS project is
226 * distributed under a <a href="https://djunits.org/docs/license.html" target="_blank">three-clause BSD-style license</a>.
227 * @author Alexander Verbraeck
228 */
229 @SuppressWarnings("checkstyle:constantname")
230 public static class Unit extends AbstractUnit<Torque.Unit, Torque>
231 {
232 /** The dimensions of torque: kgm2/s2. */
233 public static final SIUnit SI_UNIT = SIUnit.of("kgm2/s2");
234
235 /** Newton meter. */
236 public static final Torque.Unit Nm = new Torque.Unit("Nm", "newton meter", 1.0, UnitSystem.SI_DERIVED);
237
238 /** The SI or BASE unit. */
239 public static final Torque.Unit SI = Nm;
240
241 /** meter kilogram-force. */
242 public static final Torque.Unit m_kgf =
243 SI.deriveUnit("m.kgf", "meter kilogram-force", Acceleration.Unit.CONST_GRAVITY, UnitSystem.OTHER);
244
245 /** Pound foot. */
246 public static final Torque.Unit lbf_ft = SI.deriveUnit("lbf.ft", "pound-force foot",
247 Length.Unit.CONST_FT * Mass.Unit.CONST_LB * Acceleration.Unit.CONST_GRAVITY, UnitSystem.IMPERIAL);
248
249 /** Pound inch. */
250 public static final Torque.Unit lbf_in = SI.deriveUnit("lbf.in", "pound-force inch",
251 Length.Unit.CONST_IN * Mass.Unit.CONST_LB * Acceleration.Unit.CONST_GRAVITY, UnitSystem.IMPERIAL);
252
253 /**
254 * Create a new Torque unit.
255 * @param id the id or main abbreviation of the unit
256 * @param name the full name of the unit
257 * @param scaleFactorToBaseUnit the scale factor of the unit to convert it TO the base (SI) unit
258 * @param unitSystem the unit system such as SI or IMPERIAL
259 */
260 public Unit(final String id, final String name, final double scaleFactorToBaseUnit, final UnitSystem unitSystem)
261 {
262 super(id, name, new LinearScale(scaleFactorToBaseUnit), unitSystem);
263 }
264
265 /**
266 * Return a derived unit for this unit, with textual abbreviation(s) and a display abbreviation.
267 * @param textualAbbreviation the textual abbreviation of the unit, which doubles as the id
268 * @param displayAbbreviation the display abbreviation of the unit
269 * @param name the full name of the unit
270 * @param scale the scale to use to convert between this unit and the standard (e.g., SI, BASE) unit
271 * @param unitSystem unit system, e.g. SI or Imperial
272 */
273 public Unit(final String textualAbbreviation, final String displayAbbreviation, final String name, final Scale scale,
274 final UnitSystem unitSystem)
275 {
276 super(textualAbbreviation, displayAbbreviation, name, scale, unitSystem);
277 }
278
279 @Override
280 public SIUnit siUnit()
281 {
282 return SI_UNIT;
283 }
284
285 @Override
286 public Unit getBaseUnit()
287 {
288 return SI;
289 }
290
291 @Override
292 public Torque ofSi(final double si)
293 {
294 return Torque.ofSi(si);
295 }
296
297 @Override
298 public Unit deriveUnit(final String textualAbbreviation, final String displayAbbreviation, final String name,
299 final double scaleFactor, final UnitSystem unitSystem)
300 {
301 if (getScale() instanceof LinearScale ls)
302 {
303 return new Torque.Unit(textualAbbreviation, displayAbbreviation, name,
304 new LinearScale(ls.getScaleFactorToBaseUnit() * scaleFactor), unitSystem);
305 }
306 throw new UnitRuntimeException("Only possible to derive a unit from a unit with a linear scale");
307 }
308
309 }
310 }