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 * Luminous flux is the total perceived power of light emitted by a source, measured in lumens (lm).
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 LuminousFlux extends Quantity<LuminousFlux>
21 {
22 /** Constant with value zero. */
23 public static final LuminousFlux ZERO = ofSi(0.0);
24
25 /** Constant with value one. */
26 public static final LuminousFlux ONE = ofSi(1.0);
27
28 /** Constant with value NaN. */
29 @SuppressWarnings("checkstyle:constantname")
30 public static final LuminousFlux NaN = ofSi(Double.NaN);
31
32 /** Constant with value POSITIVE_INFINITY. */
33 public static final LuminousFlux POSITIVE_INFINITY = ofSi(Double.POSITIVE_INFINITY);
34
35 /** Constant with value NEGATIVE_INFINITY. */
36 public static final LuminousFlux NEGATIVE_INFINITY = ofSi(Double.NEGATIVE_INFINITY);
37
38 /** Constant with value MAX_VALUE. */
39 public static final LuminousFlux POS_MAXVALUE = ofSi(Double.MAX_VALUE);
40
41 /** Constant with value -MAX_VALUE. */
42 public static final LuminousFlux NEG_MAXVALUE = ofSi(-Double.MAX_VALUE);
43
44 /** */
45 private static final long serialVersionUID = 600L;
46
47 /**
48 * Instantiate a LuminousFlux 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 LuminousFlux(final double valueInUnit, final LuminousFlux.Unit unit)
53 {
54 super(valueInUnit, unit);
55 }
56
57 /**
58 * Return a LuminousFlux instance based on an SI value.
59 * @param si the si value
60 * @return the LuminousFlux instance based on an SI value
61 */
62 public static LuminousFlux ofSi(final double si)
63 {
64 return new LuminousFlux(si, LuminousFlux.Unit.SI);
65 }
66
67 @Override
68 public LuminousFlux instantiateSi(final double si)
69 {
70 return ofSi(si);
71 }
72
73 @Override
74 public SIUnit siUnit()
75 {
76 return LuminousFlux.Unit.SI_UNIT;
77 }
78
79 /**
80 * Returns a LuminousFlux representation of a textual representation of a value with a unit. The String representation that
81 * can be parsed is the double value in the unit, followed by a localized or English abbreviation of the unit. Spaces are
82 * allowed, but not required, between the value and the unit.
83 * @param text the textual representation to parse into a LuminousFlux
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 LuminousFlux valueOf(final String text)
89 {
90 return Quantity.valueOf(text, ZERO);
91 }
92
93 /**
94 * Returns a LuminousFlux 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 LuminousFlux of(final double valueInUnit, final String unitString)
102 {
103 return Quantity.of(valueInUnit, unitString, ZERO);
104 }
105
106 @Override
107 public LuminousFlux.Unit getDisplayUnit()
108 {
109 return (LuminousFlux.Unit) super.getDisplayUnit();
110 }
111
112 /**
113 * Calculate the division of LuminousFlux and LuminousFlux, which results in a Dimensionless quantity.
114 * @param v quantity
115 * @return quantity as a division of LuminousFlux and LuminousFlux
116 */
117 public final Dimensionless divide(final LuminousFlux v)
118 {
119 return new Dimensionless(this.si() / v.si(), Unitless.BASE);
120 }
121
122 /**
123 * Calculate the division of LuminousFlux and Area, which results in a Illuminance scalar.
124 * @param v scalar
125 * @return scalar as a division of LuminousFlux and Area
126 */
127 public final Illuminance divide(final Area v)
128 {
129 return new Illuminance(this.si() / v.si(), Illuminance.Unit.SI);
130 }
131
132 /**
133 * Calculate the division of LuminousFlux and Illuminance, which results in a Area scalar.
134 * @param v scalar
135 * @return scalar as a division of LuminousFlux and Illuminance
136 */
137 public final Area divide(final Illuminance v)
138 {
139 return new Area(this.si() / v.si(), Area.Unit.SI);
140 }
141
142 /**
143 * Calculate the division of LuminousFlux and LuminousIntensity, which results in a SolidAngle scalar.
144 * @param v scalar
145 * @return scalar as a division of LuminousFlux and LuminousIntensity
146 */
147 public final SolidAngle divide(final LuminousIntensity v)
148 {
149 return new SolidAngle(this.si() / v.si(), SolidAngle.Unit.SI);
150 }
151
152 /**
153 * Calculate the division of LuminousFlux and SolidAngle, which results in a LuminousIntensity scalar.
154 * @param v scalar
155 * @return scalar as a division of LuminousFlux and SolidAngle
156 */
157 public final LuminousIntensity divide(final SolidAngle v)
158 {
159 return new LuminousIntensity(this.si() / v.si(), LuminousIntensity.Unit.SI);
160 }
161
162 /******************************************************************************************************/
163 /********************************************** UNIT CLASS ********************************************/
164 /******************************************************************************************************/
165
166 /**
167 * LuminousFlux.Unit encodes the units of total perceived power of light emitted by a source.
168 * <p>
169 * Copyright (c) 2025-2026 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved.
170 * See for project information <a href="https://djunits.org" target="_blank">https://djunits.org</a>. The DJUNITS project is
171 * distributed under a <a href="https://djunits.org/docs/license.html" target="_blank">three-clause BSD-style license</a>.
172 * @author Alexander Verbraeck
173 */
174 @SuppressWarnings("checkstyle:constantname")
175 public static class Unit extends AbstractUnit<LuminousFlux.Unit, LuminousFlux>
176 {
177 /** The dimensions of luminous flux: cd.sr. */
178 public static final SIUnit SI_UNIT = SIUnit.of("cdsr");
179
180 /** Lumen. */
181 public static final LuminousFlux.Unit lm = new LuminousFlux.Unit("lm", "lumen", 1.0, UnitSystem.SI_DERIVED);
182
183 /** The SI or BASE unit. */
184 public static final LuminousFlux.Unit SI = lm;
185
186 /**
187 * Create a new LuminousFlux unit.
188 * @param id the id or main abbreviation of the unit
189 * @param name the full name of the unit
190 * @param scaleFactorToBaseUnit the scale factor of the unit to convert it TO the base (SI) unit
191 * @param unitSystem the unit system such as SI or IMPERIAL
192 */
193 public Unit(final String id, final String name, final double scaleFactorToBaseUnit, final UnitSystem unitSystem)
194 {
195 super(id, name, new LinearScale(scaleFactorToBaseUnit), unitSystem);
196 }
197
198 /**
199 * Return a derived unit for this unit, with textual abbreviation(s) and a display abbreviation.
200 * @param textualAbbreviation the textual abbreviation of the unit, which doubles as the id
201 * @param displayAbbreviation the display abbreviation of the unit
202 * @param name the full name of the unit
203 * @param scale the scale to use to convert between this unit and the standard (e.g., SI, BASE) unit
204 * @param unitSystem unit system, e.g. SI or Imperial
205 */
206 public Unit(final String textualAbbreviation, final String displayAbbreviation, final String name, final Scale scale,
207 final UnitSystem unitSystem)
208 {
209 super(textualAbbreviation, displayAbbreviation, name, scale, unitSystem);
210 }
211
212 @Override
213 public SIUnit siUnit()
214 {
215 return SI_UNIT;
216 }
217
218 @Override
219 public Unit getBaseUnit()
220 {
221 return SI;
222 }
223
224 @Override
225 public LuminousFlux ofSi(final double si)
226 {
227 return LuminousFlux.ofSi(si);
228 }
229
230 @Override
231 public Unit deriveUnit(final String textualAbbreviation, final String displayAbbreviation, final String name,
232 final double scaleFactor, final UnitSystem unitSystem)
233 {
234 if (getScale() instanceof LinearScale ls)
235 {
236 return new LuminousFlux.Unit(textualAbbreviation, displayAbbreviation, name,
237 new LinearScale(ls.getScaleFactorToBaseUnit() * scaleFactor), unitSystem);
238 }
239 throw new UnitRuntimeException("Only possible to derive a unit from a unit with a linear scale");
240 }
241
242 }
243 }