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.scale.LinearScale;
8 import org.djunits.unit.scale.Scale;
9 import org.djunits.unit.si.SIUnit;
10 import org.djunits.unit.system.UnitSystem;
11
12 /**
13 * Volumetric object density counts the number of objects per unit of volume, measured in number per cubic meter (/m3).
14 * <p>
15 * Copyright (c) 2025-2026 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved. See
16 * for project information <a href="https://djunits.org" target="_blank">https://djunits.org</a>. The DJUNITS project is
17 * distributed under a <a href="https://djunits.org/docs/license.html" target="_blank">three-clause BSD-style license</a>.
18 * @author Alexander Verbraeck
19 */
20 public class VolumetricObjectDensity extends Quantity<VolumetricObjectDensity>
21 {
22 /** Constant with value zero. */
23 public static final VolumetricObjectDensity ZERO = ofSi(0.0);
24
25 /** Constant with value one. */
26 public static final VolumetricObjectDensity ONE = ofSi(1.0);
27
28 /** Constant with value NaN. */
29 @SuppressWarnings("checkstyle:constantname")
30 public static final VolumetricObjectDensity NaN = ofSi(Double.NaN);
31
32 /** Constant with value POSITIVE_INFINITY. */
33 public static final VolumetricObjectDensity POSITIVE_INFINITY = ofSi(Double.POSITIVE_INFINITY);
34
35 /** Constant with value NEGATIVE_INFINITY. */
36 public static final VolumetricObjectDensity NEGATIVE_INFINITY = ofSi(Double.NEGATIVE_INFINITY);
37
38 /** Constant with value MAX_VALUE. */
39 public static final VolumetricObjectDensity POS_MAXVALUE = ofSi(Double.MAX_VALUE);
40
41 /** Constant with value -MAX_VALUE. */
42 public static final VolumetricObjectDensity NEG_MAXVALUE = ofSi(-Double.MAX_VALUE);
43
44 /** */
45 private static final long serialVersionUID = 600L;
46
47 /**
48 * Instantiate a VolumetricObjectDensity quantity with a unit.
49 * @param valueInUnit the value, expressed in the unit
50 * @param unit the unit in which the value is expressed
51 */
52 public VolumetricObjectDensity(final double valueInUnit, final VolumetricObjectDensity.Unit unit)
53 {
54 super(valueInUnit, unit);
55 }
56
57 /**
58 * Return a VolumetricObjectDensity instance based on an SI value.
59 * @param si the si value
60 * @return the VolumetricObjectDensity instance based on an SI value
61 */
62 public static VolumetricObjectDensity ofSi(final double si)
63 {
64 return new VolumetricObjectDensity(si, VolumetricObjectDensity.Unit.SI);
65 }
66
67 @Override
68 public VolumetricObjectDensity instantiateSi(final double si)
69 {
70 return ofSi(si);
71 }
72
73 @Override
74 public SIUnit siUnit()
75 {
76 return VolumetricObjectDensity.Unit.SI_UNIT;
77 }
78
79 /**
80 * Returns a VolumetricObjectDensity representation of a textual representation of a value with a unit. The String
81 * representation that can be parsed is the double value in the unit, followed by a localized or English abbreviation of the
82 * unit. Spaces are allowed, but not required, between the value and the unit.
83 * @param text the textual representation to parse into a VolumetricObjectDensity
84 * @return the Scalar representation of the value in its unit
85 * @throws IllegalArgumentException when the text cannot be parsed
86 * @throws NullPointerException when the text argument is null
87 */
88 public static VolumetricObjectDensity valueOf(final String text)
89 {
90 return Quantity.valueOf(text, ZERO);
91 }
92
93 /**
94 * Returns a VolumetricObjectDensity based on a value and the textual representation of the unit, which can be localized.
95 * @param valueInUnit the value, expressed in the unit as given by unitString
96 * @param unitString the textual representation of the unit
97 * @return the Scalar representation of the value in its unit
98 * @throws IllegalArgumentException when the unit cannot be parsed or is incorrect
99 * @throws NullPointerException when the unitString argument is null
100 */
101 public static VolumetricObjectDensity of(final double valueInUnit, final String unitString)
102 {
103 return Quantity.of(valueInUnit, unitString, ZERO);
104 }
105
106 @Override
107 public VolumetricObjectDensity.Unit getDisplayUnit()
108 {
109 return (VolumetricObjectDensity.Unit) super.getDisplayUnit();
110 }
111
112 /**
113 * Multiplies this volumetric object density by a volume to yield a dimensionless count.
114 * <p>
115 * Formula: (1/m³) x m³ = 1.
116 * @param volume the volume multiplier; must not be {@code null}.
117 * @return the resulting dimensionless count in SI (1).
118 * @throws NullPointerException if {@code volume} is {@code null}.
119 */
120 public final Dimensionless multiply(final Volume volume)
121 {
122 return new Dimensionless(this.si() * volume.si(), Unitless.BASE);
123 }
124
125 /**
126 * Multiplies this volumetric object density by an area to yield a linear object density.
127 * <p>
128 * Formula: (1/m³) x m² = 1/m.
129 * @param area the area multiplier; must not be {@code null}.
130 * @return the resulting linear object density in SI (1/m).
131 * @throws NullPointerException if {@code area} is {@code null}.
132 */
133 public final LinearObjectDensity multiply(final Area area)
134 {
135 return new LinearObjectDensity(this.si() * area.si(), LinearObjectDensity.Unit.SI);
136 }
137
138 /**
139 * Multiplies this volumetric object density by a length to yield an areal object density.
140 * <p>
141 * Formula: (1/m³) x m = 1/m².
142 * @param length the length multiplier; must not be {@code null}.
143 * @return the resulting areal object density in SI (1/m²).
144 * @throws NullPointerException if {@code length} is {@code null}.
145 */
146 public final ArealObjectDensity multiply(final Length length)
147 {
148 return new ArealObjectDensity(this.si() * length.si(), ArealObjectDensity.Unit.SI);
149 }
150
151 /**
152 * Divides this volumetric object density by a linear object density to yield an areal object density.
153 * <p>
154 * Formula: (1/m³) / (1/m) = 1/m².
155 * @param lod the linear object density divisor; must not be {@code null}.
156 * @return the resulting areal object density in SI (1/m²).
157 * @throws NullPointerException if {@code lod} is {@code null}.
158 */
159 public final ArealObjectDensity divide(final LinearObjectDensity lod)
160 {
161 return new ArealObjectDensity(this.si() / lod.si(), ArealObjectDensity.Unit.SI);
162 }
163
164 /**
165 * Divides this volumetric object density by an areal object density to yield a linear object density.
166 * <p>
167 * Formula: (1/m³) / (1/m²) = 1/m.
168 * @param aod the areal object density divisor; must not be {@code null}.
169 * @return the resulting linear object density in SI (1/m).
170 * @throws NullPointerException if {@code aod} is {@code null}.
171 */
172 public final LinearObjectDensity divide(final ArealObjectDensity aod)
173 {
174 return new LinearObjectDensity(this.si() / aod.si(), LinearObjectDensity.Unit.SI);
175 }
176
177 /**
178 * Divides this volumetric object density by another volumetric object density to yield a dimensionless ratio.
179 * <p>
180 * Formula: (1/m³) / (1/m³) = 1.
181 * @param other the volumetric object density divisor; must not be {@code null}.
182 * @return the resulting dimensionless ratio in SI (1).
183 * @throws NullPointerException if {@code other} is {@code null}.
184 */
185 public final Dimensionless divide(final VolumetricObjectDensity other)
186 {
187 return new Dimensionless(this.si() / other.si(), Unitless.BASE);
188 }
189
190 @Override
191 public Volume reciprocal()
192 {
193 return Volume.ofSi(1.0 / this.si());
194 }
195
196 /******************************************************************************************************/
197 /********************************************** UNIT CLASS ********************************************/
198 /******************************************************************************************************/
199
200 /**
201 * VolumetricObjectDensity.Unit encodes the unit for number of objects per unit of volume.
202 * <p>
203 * Copyright (c) 2025-2026 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved.
204 * See for project information <a href="https://djunits.org" target="_blank">https://djunits.org</a>. The DJUNITS project is
205 * distributed under a <a href="https://djunits.org/docs/license.html" target="_blank">three-clause BSD-style license</a>.
206 * @author Alexander Verbraeck
207 */
208 @SuppressWarnings("checkstyle:constantname")
209 public static class Unit extends AbstractUnit<VolumetricObjectDensity.Unit, VolumetricObjectDensity>
210 {
211 /** The dimensions of the number of objects per unit of volume: per cubic meter (/m3). */
212 public static final SIUnit SI_UNIT = SIUnit.of("/m3");
213
214 /** per cubic meter. */
215 public static final VolumetricObjectDensity.Unit per_m3 =
216 new VolumetricObjectDensity.Unit("/m3", "per cubic meter", 1.0, UnitSystem.SI_DERIVED);
217
218 /** The SI or BASE unit. */
219 public static final VolumetricObjectDensity.Unit SI = per_m3;
220
221 /**
222 * Create a new VolumetricObjectDensity unit.
223 * @param id the id or main abbreviation of the unit
224 * @param name the full name of the unit
225 * @param scaleFactorToBaseUnit the scale factor of the unit to convert it TO the base (SI) unit
226 * @param unitSystem the unit system such as SI or IMPERIAL
227 */
228 public Unit(final String id, final String name, final double scaleFactorToBaseUnit, final UnitSystem unitSystem)
229 {
230 super(id, name, new LinearScale(scaleFactorToBaseUnit), unitSystem);
231 }
232
233 /**
234 * Return a derived unit for this unit, with textual abbreviation(s) and a display abbreviation.
235 * @param textualAbbreviation the textual abbreviation of the unit, which doubles as the id
236 * @param displayAbbreviation the display abbreviation of the unit
237 * @param name the full name of the unit
238 * @param scale the scale to use to convert between this unit and the standard (e.g., SI, BASE) unit
239 * @param unitSystem unit system, e.g. SI or Imperial
240 */
241 public Unit(final String textualAbbreviation, final String displayAbbreviation, final String name, final Scale scale,
242 final UnitSystem unitSystem)
243 {
244 super(textualAbbreviation, displayAbbreviation, name, scale, unitSystem);
245 }
246
247 @Override
248 public SIUnit siUnit()
249 {
250 return SI_UNIT;
251 }
252
253 @Override
254 public Unit getBaseUnit()
255 {
256 return SI;
257 }
258
259 @Override
260 public VolumetricObjectDensity ofSi(final double si)
261 {
262 return VolumetricObjectDensity.ofSi(si);
263 }
264
265 @Override
266 public Unit deriveUnit(final String textualAbbreviation, final String displayAbbreviation, final String name,
267 final double scaleFactor, final UnitSystem unitSystem)
268 {
269 if (getScale() instanceof LinearScale ls)
270 {
271 return new VolumetricObjectDensity.Unit(textualAbbreviation, displayAbbreviation, name,
272 new LinearScale(ls.getScaleFactorToBaseUnit() * scaleFactor), unitSystem);
273 }
274 throw new UnitRuntimeException("Only possible to derive a unit from a unit with a linear scale");
275 }
276
277 }
278 }