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, LuminousFlux.Unit>
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 value the value, expressed in the unit
51 * @param unit the unit in which the value is expressed
52 */
53 public LuminousFlux(final double value, final LuminousFlux.Unit unit)
54 {
55 super(value, unit);
56 }
57
58 /**
59 * Instantiate a LuminousFlux 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 LuminousFlux(final double value, final String abbreviation)
64 {
65 this(value, 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 instantiate(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 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 LuminousFlux of(final double value, final String unitString)
123 {
124 return Quantity.of(value, unitString, ZERO);
125 }
126
127 /**
128 * Calculate the division of LuminousFlux and LuminousFlux, which results in a Dimensionless quantity.
129 * @param v quantity
130 * @return quantity as a division of LuminousFlux and LuminousFlux
131 */
132 public final Dimensionless divide(final LuminousFlux v)
133 {
134 return new Dimensionless(this.si() / v.si(), Unitless.BASE);
135 }
136
137 /**
138 * Calculate the division of LuminousFlux and Area, which results in a Illuminance scalar.
139 * @param v scalar
140 * @return scalar as a division of LuminousFlux and Area
141 */
142 public final Illuminance divide(final Area v)
143 {
144 return new Illuminance(this.si() / v.si(), Illuminance.Unit.SI);
145 }
146
147 /**
148 * Calculate the division of LuminousFlux and Illuminance, which results in a Area scalar.
149 * @param v scalar
150 * @return scalar as a division of LuminousFlux and Illuminance
151 */
152 public final Area divide(final Illuminance v)
153 {
154 return new Area(this.si() / v.si(), Area.Unit.SI);
155 }
156
157 /**
158 * Calculate the division of LuminousFlux and LuminousIntensity, which results in a SolidAngle scalar.
159 * @param v scalar
160 * @return scalar as a division of LuminousFlux and LuminousIntensity
161 */
162 public final SolidAngle divide(final LuminousIntensity v)
163 {
164 return new SolidAngle(this.si() / v.si(), SolidAngle.Unit.SI);
165 }
166
167 /**
168 * Calculate the division of LuminousFlux and SolidAngle, which results in a LuminousIntensity scalar.
169 * @param v scalar
170 * @return scalar as a division of LuminousFlux and SolidAngle
171 */
172 public final LuminousIntensity divide(final SolidAngle v)
173 {
174 return new LuminousIntensity(this.si() / v.si(), LuminousIntensity.Unit.SI);
175 }
176
177 /******************************************************************************************************/
178 /********************************************** UNIT CLASS ********************************************/
179 /******************************************************************************************************/
180
181 /**
182 * LuminousFlux.Unit encodes the units of total perceived power of light emitted by a source.
183 * <p>
184 * Copyright (c) 2025-2026 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved.
185 * See for project information <a href="https://djunits.org" target="_blank">https://djunits.org</a>. The DJUNITS project is
186 * distributed under a <a href="https://djunits.org/docs/license.html" target="_blank">three-clause BSD-style license</a>.
187 * @author Alexander Verbraeck
188 */
189 @SuppressWarnings("checkstyle:constantname")
190 public static class Unit extends AbstractUnit<LuminousFlux.Unit, LuminousFlux>
191 {
192 /** The dimensions of luminous flux: cd.sr. */
193 public static final SIUnit SI_UNIT = SIUnit.of("cdsr");
194
195 /** Lumen. */
196 public static final LuminousFlux.Unit lm = new LuminousFlux.Unit("lm", "lumen", 1.0, UnitSystem.SI_DERIVED);
197
198 /** The SI or BASE unit. */
199 public static final LuminousFlux.Unit SI = lm;
200
201 /**
202 * Create a new LuminousFlux unit.
203 * @param id the id or main abbreviation of the unit
204 * @param name the full name of the unit
205 * @param scaleFactorToBaseUnit the scale factor of the unit to convert it TO the base (SI) unit
206 * @param unitSystem the unit system such as SI or IMPERIAL
207 */
208 public Unit(final String id, final String name, final double scaleFactorToBaseUnit, final UnitSystem unitSystem)
209 {
210 super(id, name, new LinearScale(scaleFactorToBaseUnit), unitSystem);
211 }
212
213 /**
214 * Return a derived unit for this unit, with textual abbreviation(s) and a display abbreviation.
215 * @param textualAbbreviation the textual abbreviation of the unit, which doubles as the id
216 * @param displayAbbreviation the display abbreviation of the unit
217 * @param name the full name of the unit
218 * @param scale the scale to use to convert between this unit and the standard (e.g., SI, BASE) unit
219 * @param unitSystem unit system, e.g. SI or Imperial
220 */
221 public Unit(final String textualAbbreviation, final String displayAbbreviation, final String name, final Scale scale,
222 final UnitSystem unitSystem)
223 {
224 super(textualAbbreviation, displayAbbreviation, name, scale, unitSystem);
225 }
226
227 @Override
228 public SIUnit siUnit()
229 {
230 return SI_UNIT;
231 }
232
233 @Override
234 public Unit getBaseUnit()
235 {
236 return SI;
237 }
238
239 @Override
240 public LuminousFlux ofSi(final double si)
241 {
242 return LuminousFlux.ofSi(si);
243 }
244
245 @Override
246 public Unit deriveUnit(final String textualAbbreviation, final String displayAbbreviation, final String name,
247 final double scaleFactor, final UnitSystem unitSystem)
248 {
249 if (getScale() instanceof LinearScale ls)
250 {
251 return new LuminousFlux.Unit(textualAbbreviation, displayAbbreviation, name,
252 new LinearScale(ls.getScaleFactorToBaseUnit() * scaleFactor), unitSystem);
253 }
254 throw new UnitRuntimeException("Only possible to derive a unit from a unit with a linear scale");
255 }
256
257 }
258 }