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 * Luminous flux is the total perceived power of light emitted by a source, measured in lumens (lm).
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 LuminousFlux extends Quantity<LuminousFlux>
22 {
23 /** Constant with value zero. */
24 public static final LuminousFlux ZERO = LuminousFlux.ofSi(0.0);
25
26 /** Constant with value one. */
27 public static final LuminousFlux ONE = LuminousFlux.ofSi(1.0);
28
29 /** Constant with value NaN. */
30 @SuppressWarnings("checkstyle:constantname")
31 public static final LuminousFlux NaN = LuminousFlux.ofSi(Double.NaN);
32
33 /** Constant with value POSITIVE_INFINITY. */
34 public static final LuminousFlux POSITIVE_INFINITY = LuminousFlux.ofSi(Double.POSITIVE_INFINITY);
35
36 /** Constant with value NEGATIVE_INFINITY. */
37 public static final LuminousFlux NEGATIVE_INFINITY = LuminousFlux.ofSi(Double.NEGATIVE_INFINITY);
38
39 /** Constant with value MAX_VALUE. */
40 public static final LuminousFlux POS_MAXVALUE = LuminousFlux.ofSi(Double.MAX_VALUE);
41
42 /** Constant with value -MAX_VALUE. */
43 public static final LuminousFlux NEG_MAXVALUE = LuminousFlux.ofSi(-Double.MAX_VALUE);
44
45 /** */
46 private static final long serialVersionUID = 600L;
47
48 /**
49 * Instantiate a LuminousFlux 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 LuminousFlux(final double valueInUnit, final LuminousFlux.Unit unit)
54 {
55 super(valueInUnit, unit);
56 }
57
58 /**
59 * Instantiate a LuminousFlux quantity with a unit, expressed as a String.
60 * @param valueInUnit the value, expressed in the unit
61 * @param abbreviation the String abbreviation of the unit in which the value is expressed
62 */
63 public LuminousFlux(final double valueInUnit, final String abbreviation)
64 {
65 this(valueInUnit, Units.resolve(LuminousFlux.Unit.class, abbreviation));
66 }
67
68 /**
69 * Construct LuminousFlux quantity.
70 * @param value Scalar from which to construct this instance
71 */
72 public LuminousFlux(final LuminousFlux value)
73 {
74 super(value.si(), LuminousFlux.Unit.SI);
75 setDisplayUnit(value.getDisplayUnit());
76 }
77
78 /**
79 * Return a LuminousFlux instance based on an SI value.
80 * @param si the si value
81 * @return the LuminousFlux instance based on an SI value
82 */
83 public static LuminousFlux ofSi(final double si)
84 {
85 return new LuminousFlux(si, LuminousFlux.Unit.SI);
86 }
87
88 @Override
89 public LuminousFlux instantiateSi(final double si)
90 {
91 return ofSi(si);
92 }
93
94 @Override
95 public SIUnit siUnit()
96 {
97 return LuminousFlux.Unit.SI_UNIT;
98 }
99
100 /**
101 * Returns a LuminousFlux representation of a textual representation of a value with a unit. The String representation that
102 * can be parsed is the double value in the unit, followed by a localized or English abbreviation of the unit. Spaces are
103 * allowed, but not required, between the value and the unit.
104 * @param text the textual representation to parse into a LuminousFlux
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 LuminousFlux valueOf(final String text)
110 {
111 return Quantity.valueOf(text, ZERO);
112 }
113
114 /**
115 * Returns a LuminousFlux based on a value and the textual representation of the unit, which can be localized.
116 * @param valueInUnit the value, expressed in the unit as given by unitString
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 LuminousFlux of(final double valueInUnit, final String unitString)
123 {
124 return Quantity.of(valueInUnit, unitString, ZERO);
125 }
126
127 @Override
128 public LuminousFlux.Unit getDisplayUnit()
129 {
130 return (LuminousFlux.Unit) super.getDisplayUnit();
131 }
132
133 /**
134 * Calculate the division of LuminousFlux and LuminousFlux, which results in a Dimensionless quantity.
135 * @param v quantity
136 * @return quantity as a division of LuminousFlux and LuminousFlux
137 */
138 public final Dimensionless divide(final LuminousFlux v)
139 {
140 return new Dimensionless(this.si() / v.si(), Unitless.BASE);
141 }
142
143 /**
144 * Calculate the division of LuminousFlux and Area, which results in a Illuminance scalar.
145 * @param v scalar
146 * @return scalar as a division of LuminousFlux and Area
147 */
148 public final Illuminance divide(final Area v)
149 {
150 return new Illuminance(this.si() / v.si(), Illuminance.Unit.SI);
151 }
152
153 /**
154 * Calculate the division of LuminousFlux and Illuminance, which results in a Area scalar.
155 * @param v scalar
156 * @return scalar as a division of LuminousFlux and Illuminance
157 */
158 public final Area divide(final Illuminance v)
159 {
160 return new Area(this.si() / v.si(), Area.Unit.SI);
161 }
162
163 /**
164 * Calculate the division of LuminousFlux and LuminousIntensity, which results in a SolidAngle scalar.
165 * @param v scalar
166 * @return scalar as a division of LuminousFlux and LuminousIntensity
167 */
168 public final SolidAngle divide(final LuminousIntensity v)
169 {
170 return new SolidAngle(this.si() / v.si(), SolidAngle.Unit.SI);
171 }
172
173 /**
174 * Calculate the division of LuminousFlux and SolidAngle, which results in a LuminousIntensity scalar.
175 * @param v scalar
176 * @return scalar as a division of LuminousFlux and SolidAngle
177 */
178 public final LuminousIntensity divide(final SolidAngle v)
179 {
180 return new LuminousIntensity(this.si() / v.si(), LuminousIntensity.Unit.SI);
181 }
182
183 /******************************************************************************************************/
184 /********************************************** UNIT CLASS ********************************************/
185 /******************************************************************************************************/
186
187 /**
188 * LuminousFlux.Unit encodes the units of total perceived power of light emitted by a source.
189 * <p>
190 * Copyright (c) 2025-2026 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved.
191 * See for project information <a href="https://djunits.org" target="_blank">https://djunits.org</a>. The DJUNITS project is
192 * distributed under a <a href="https://djunits.org/docs/license.html" target="_blank">three-clause BSD-style license</a>.
193 * @author Alexander Verbraeck
194 */
195 @SuppressWarnings("checkstyle:constantname")
196 public static class Unit extends AbstractUnit<LuminousFlux.Unit, LuminousFlux>
197 {
198 /** The dimensions of luminous flux: cd.sr. */
199 public static final SIUnit SI_UNIT = SIUnit.of("cdsr");
200
201 /** Lumen. */
202 public static final LuminousFlux.Unit lm = new LuminousFlux.Unit("lm", "lumen", 1.0, UnitSystem.SI_DERIVED);
203
204 /** The SI or BASE unit. */
205 public static final LuminousFlux.Unit SI = lm;
206
207 /**
208 * Create a new LuminousFlux unit.
209 * @param id the id or main abbreviation of the unit
210 * @param name the full name of the unit
211 * @param scaleFactorToBaseUnit the scale factor of the unit to convert it TO the base (SI) unit
212 * @param unitSystem the unit system such as SI or IMPERIAL
213 */
214 public Unit(final String id, final String name, final double scaleFactorToBaseUnit, final UnitSystem unitSystem)
215 {
216 super(id, name, new LinearScale(scaleFactorToBaseUnit), unitSystem);
217 }
218
219 /**
220 * Return a derived unit for this unit, with textual abbreviation(s) and a display abbreviation.
221 * @param textualAbbreviation the textual abbreviation of the unit, which doubles as the id
222 * @param displayAbbreviation the display abbreviation of the unit
223 * @param name the full name of the unit
224 * @param scale the scale to use to convert between this unit and the standard (e.g., SI, BASE) unit
225 * @param unitSystem unit system, e.g. SI or Imperial
226 */
227 public Unit(final String textualAbbreviation, final String displayAbbreviation, final String name, final Scale scale,
228 final UnitSystem unitSystem)
229 {
230 super(textualAbbreviation, displayAbbreviation, name, scale, unitSystem);
231 }
232
233 @Override
234 public SIUnit siUnit()
235 {
236 return SI_UNIT;
237 }
238
239 @Override
240 public Unit getBaseUnit()
241 {
242 return SI;
243 }
244
245 @Override
246 public LuminousFlux ofSi(final double si)
247 {
248 return LuminousFlux.ofSi(si);
249 }
250
251 @Override
252 public Unit deriveUnit(final String textualAbbreviation, final String displayAbbreviation, final String name,
253 final double scaleFactor, final UnitSystem unitSystem)
254 {
255 if (getScale() instanceof LinearScale ls)
256 {
257 return new LuminousFlux.Unit(textualAbbreviation, displayAbbreviation, name,
258 new LinearScale(ls.getScaleFactorToBaseUnit() * scaleFactor), unitSystem);
259 }
260 throw new UnitRuntimeException("Only possible to derive a unit from a unit with a linear scale");
261 }
262
263 }
264 }