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 * Acceleration is the rate of change of velocity over time, measured in meters per second squared (m/s2).
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 Acceleration extends Quantity<Acceleration>
23 {
24 /** Constant with value zero. */
25 public static final Acceleration ZERO = ofSi(0.0);
26
27 /** Constant with value one. */
28 public static final Acceleration ONE = ofSi(1.0);
29
30 /** Constant with value NaN. */
31 @SuppressWarnings("checkstyle:constantname")
32 public static final Acceleration NaN = ofSi(Double.NaN);
33
34 /** Constant with value POSITIVE_INFINITY. */
35 public static final Acceleration POSITIVE_INFINITY = ofSi(Double.POSITIVE_INFINITY);
36
37 /** Constant with value NEGATIVE_INFINITY. */
38 public static final Acceleration NEGATIVE_INFINITY = ofSi(Double.NEGATIVE_INFINITY);
39
40 /** Constant with value MAX_VALUE. */
41 public static final Acceleration POS_MAXVALUE = ofSi(Double.MAX_VALUE);
42
43 /** Constant with value -MAX_VALUE. */
44 public static final Acceleration NEG_MAXVALUE = ofSi(-Double.MAX_VALUE);
45
46 /** */
47 private static final long serialVersionUID = 600L;
48
49 /**
50 * Instantiate a Acceleration 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 Acceleration(final double value, final Acceleration.Unit displayUnit, final boolean useSi)
56 {
57 super(value, displayUnit, useSi);
58 }
59
60 /**
61 * Instantiate a Acceleration 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 Acceleration(final double valueInUnit, final Acceleration.Unit unit)
66 {
67 this(valueInUnit, unit, false);
68 }
69
70 /**
71 * Return a Acceleration instance based on an SI value.
72 * @param si the si value
73 * @return the Acceleration instance based on an SI value
74 */
75 public static Acceleration ofSi(final double si)
76 {
77 return new Acceleration(si, Acceleration.Unit.SI, true);
78 }
79
80 /**
81 * Instantiate a Acceleration 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 Acceleration instance based on an SI value with the given display unit
85 */
86 public static Acceleration ofSi(final double siValue, final Acceleration.Unit displayUnit)
87 {
88 return new Acceleration(siValue, displayUnit, true);
89 }
90
91 @Override
92 public Acceleration instantiateSi(final double siValue, final UnitInterface<Acceleration> displayUnit)
93 {
94 return new Acceleration(siValue, (Acceleration.Unit) displayUnit, true);
95 }
96
97 /**
98 * Returns a Acceleration representation of a textual representation of a value with a unit. The String representation that
99 * can be parsed is the double value in the unit, followed by a localized or English abbreviation of the unit. Spaces are
100 * allowed, but not required, between the value and the unit.
101 * @param text the textual representation to parse into a Acceleration
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 Acceleration valueOf(final String text)
107 {
108 return Quantity.valueOf(text, ZERO);
109 }
110
111 /**
112 * Returns a Acceleration 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 Acceleration representation of the value in its unit
116 */
117 public static Acceleration of(final double valueInUnit, final Acceleration.Unit unit)
118 {
119 return new Acceleration(valueInUnit, unit);
120 }
121
122 /**
123 * Returns a Acceleration 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 Acceleration of(final double valueInUnit, final String unitString)
131 {
132 return Quantity.of(valueInUnit, unitString, ZERO);
133 }
134
135 @Override
136 public Acceleration.Unit getDisplayUnit()
137 {
138 return (Acceleration.Unit) super.getDisplayUnit();
139 }
140
141 /**
142 * Calculate the division of Acceleration and Acceleration, which results in a Dimensionless scalar.
143 * @param v scalar
144 * @return scalar as a division of Acceleration and Acceleration
145 */
146 public Dimensionless divide(final Acceleration v)
147 {
148 return new Dimensionless(this.si() / v.si(), Unitless.BASE);
149 }
150
151 /**
152 * Calculate the multiplication of Acceleration and Mass, which results in a Force scalar.
153 * @param v scalar
154 * @return scalar as a multiplication of Acceleration and Mass
155 */
156 public Force multiply(final Mass v)
157 {
158 return new Force(this.si() * v.si(), Force.Unit.SI);
159 }
160
161 /**
162 * Calculate the multiplication of Acceleration and Duration, which results in a Speed scalar.
163 * @param v scalar
164 * @return scalar as a multiplication of Acceleration and Duration
165 */
166 public Speed multiply(final Duration v)
167 {
168 return new Speed(this.si() * v.si(), Speed.Unit.SI);
169 }
170
171 /**
172 * Calculate the division of Acceleration and Frequency, which results in a Speed scalar.
173 * @param v scalar
174 * @return scalar as a division of Acceleration and Frequency
175 */
176 public Speed divide(final Frequency v)
177 {
178 return new Speed(this.si() / v.si(), Speed.Unit.SI);
179 }
180
181 /**
182 * Calculate the division of Acceleration and Speed, which results in a Frequency scalar.
183 * @param v scalar
184 * @return scalar as a division of Acceleration and Speed
185 */
186 public Frequency divide(final Speed v)
187 {
188 return new Frequency(this.si() / v.si(), Frequency.Unit.SI);
189 }
190
191 /**
192 * Calculate the multiplication of Acceleration and Momentum, which results in a Power scalar.
193 * @param v scalar
194 * @return scalar as a multiplication of Acceleration and Momentum
195 */
196 public Power multiply(final Momentum v)
197 {
198 return new Power(this.si() * v.si(), Power.Unit.SI);
199 }
200
201 /******************************************************************************************************/
202 /********************************************** UNIT CLASS ********************************************/
203 /******************************************************************************************************/
204
205 /**
206 * Acceleration.Unit encodes the units of acceleration.
207 * <p>
208 * Copyright (c) 2025-2026 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved.
209 * See for project information <a href="https://djunits.org" target="_blank">https://djunits.org</a>. The DJUNITS project is
210 * distributed under a <a href="https://djunits.org/docs/license.html" target="_blank">three-clause BSD-style license</a>.
211 * @author Alexander Verbraeck
212 */
213 @SuppressWarnings("checkstyle:constantname")
214 public static class Unit extends AbstractUnit<Acceleration>
215 {
216 /** Constant for standard gravity. */
217 public static final double CONST_GRAVITY = 9.80665;
218
219 /** The dimensions of Acceleration: m/s2. */
220 public static final SIUnit SI_UNIT = SIUnit.of("m/s2");
221
222 /** m/s2. */
223 public static final Acceleration.Unit m_s2 =
224 new Acceleration.Unit("m/s2", "meter per second squared", 1.0, UnitSystem.SI_DERIVED);
225
226 /** The SI or BASE unit. */
227 public static final Acceleration.Unit SI = m_s2;
228
229 /** km/h2. */
230 public static final Acceleration.Unit km_h2 = new Acceleration.Unit("km/h2", "kilometer per hour squared",
231 1000.0 / (3600.0 * 3600.0), UnitSystem.SI_ACCEPTED);
232
233 /** ft/s2. */
234 public static final Acceleration.Unit ft_s2 =
235 new Acceleration.Unit("ft/s2", "foot per second squared", Length.Unit.CONST_FT, UnitSystem.IMPERIAL);
236
237 /** in/s2. */
238 public static final Acceleration.Unit in_s2 =
239 new Acceleration.Unit("in/s2", "inch per second squared", Length.Unit.CONST_IN, UnitSystem.IMPERIAL);
240
241 /** mi/h2. */
242 public static final Acceleration.Unit mi_h2 = new Acceleration.Unit("mi/h2", "mile per hour squared",
243 Length.Unit.CONST_MI / (3600.0 * 3600.0), UnitSystem.IMPERIAL);
244
245 /** mi/s2. */
246 public static final Acceleration.Unit mi_s2 =
247 new Acceleration.Unit("mi/s2", "mile per second squared", Length.Unit.CONST_MI, UnitSystem.IMPERIAL);
248
249 /** kt/s = Nautical Mile / h / s. */
250 public static final Acceleration.Unit kt_s =
251 new Acceleration.Unit("kt/s", "knot per second", Length.Unit.CONST_NM / 3600.0, UnitSystem.OTHER);
252
253 /** mi/h/s. */
254 public static final Acceleration.Unit mi_h_s =
255 new Acceleration.Unit("mi/h/s", "mile per hour per second", Length.Unit.CONST_MI / 3600.0, UnitSystem.IMPERIAL);
256
257 /** The standard gravity. */
258 public static final Acceleration.Unit g =
259 new Acceleration.Unit("g", "standard gravity", CONST_GRAVITY, UnitSystem.OTHER);
260
261 /** Gal or cm/s. */
262 public static final Acceleration.Unit Gal = new Acceleration.Unit("Gal", "gal", 0.01, UnitSystem.CGS);
263
264 /**
265 * Create a new Acceleration unit.
266 * @param id the id or main abbreviation of the unit
267 * @param name the full name of the unit
268 * @param scaleFactorToBaseUnit the scale factor of the unit to convert it TO the base (SI) unit
269 * @param unitSystem the unit system such as SI or IMPERIAL
270 */
271 public Unit(final String id, final String name, final double scaleFactorToBaseUnit, final UnitSystem unitSystem)
272 {
273 super(id, name, scaleFactorToBaseUnit, unitSystem);
274 }
275
276 /**
277 * Return a derived unit for this unit, with textual abbreviation(s) and a display abbreviation.
278 * @param textualAbbreviation the textual abbreviation of the unit, which doubles as the id
279 * @param displayAbbreviation the display abbreviation of the unit
280 * @param name the full name of the unit
281 * @param scale the scale to use to convert from this unit to the standard (e.g., SI, BASE) unit
282 * @param unitSystem unit system, e.g. SI or Imperial
283 * @param siPrefix the SI Prefix of this unit
284 */
285 public Unit(final String textualAbbreviation, final String displayAbbreviation, final String name, final Scale scale,
286 final UnitSystem unitSystem, final SIPrefix siPrefix)
287 {
288 super(textualAbbreviation, displayAbbreviation, name, scale, unitSystem, siPrefix);
289 }
290
291 @Override
292 public SIUnit siUnit()
293 {
294 return SI_UNIT;
295 }
296
297 @Override
298 public Unit getBaseUnit()
299 {
300 return SI;
301 }
302
303 @Override
304 public Acceleration ofSi(final double si, final UnitInterface<Acceleration> displayUnit)
305 {
306 return new Acceleration(si, (Unit) displayUnit, true);
307 }
308
309 @Override
310 public Acceleration.Unit deriveUnit(final String textualAbbreviation, final String displayAbbreviation,
311 final String name, final double scaleFactor, final UnitSystem unitSystem, final SIPrefix siPrefix)
312 {
313 if (getScale() instanceof LinearScale ls)
314 {
315 return new Acceleration.Unit(textualAbbreviation, displayAbbreviation, name,
316 new LinearScale(ls.getScaleFactorToBaseUnit() * scaleFactor), unitSystem, siPrefix);
317 }
318 throw new UnitRuntimeException("Only possible to derive a unit from a unit with a linear scale");
319 }
320
321 }
322
323 }