1 package org.djunits.quantity;
2
3 import org.djunits.quantity.def.Quantity;
4 import org.djunits.unit.Unitless;
5 import org.djunits.unit.si.SIUnit;
6
7 /**
8 * Dimensionless quantity.
9 * <p>
10 * Copyright (c) 2025-2026 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved. See
11 * for project information <a href="https://djunits.org" target="_blank">https://djunits.org</a>. The DJUNITS project is
12 * distributed under a <a href="https://djunits.org/docs/license.html" target="_blank">three-clause BSD-style license</a>.
13 * @author Alexander Verbraeck
14 */
15 public class Dimensionless extends Quantity<Dimensionless>
16 {
17 /** Constant with value zero. */
18 public static final Dimensionless ZERO = ofSi(0.0);
19
20 /** Constant with value one. */
21 public static final Dimensionless ONE = ofSi(1.0);
22
23 /** Constant with value NaN. */
24 @SuppressWarnings("checkstyle:constantname")
25 public static final Dimensionless NaN = ofSi(Double.NaN);
26
27 /** Constant with value POSITIVE_INFINITY. */
28 public static final Dimensionless POSITIVE_INFINITY = ofSi(Double.POSITIVE_INFINITY);
29
30 /** Constant with value NEGATIVE_INFINITY. */
31 public static final Dimensionless NEGATIVE_INFINITY = ofSi(Double.NEGATIVE_INFINITY);
32
33 /** Constant with value MAX_VALUE. */
34 public static final Dimensionless POS_MAXVALUE = ofSi(Double.MAX_VALUE);
35
36 /** Constant with value -MAX_VALUE. */
37 public static final Dimensionless NEG_MAXVALUE = ofSi(-Double.MAX_VALUE);
38
39 /** */
40 private static final long serialVersionUID = 600L;
41
42 /**
43 * Instantiate a Dimensionless quantity with a unit.
44 * @param valueInUnit the value, expressed in the unit
45 * @param unit the unit in which the value is expressed
46 */
47 public Dimensionless(final double valueInUnit, final Unitless unit)
48 {
49 super(valueInUnit, unit);
50 }
51
52 /**
53 * Return a Dimensionless instance based on an SI value.
54 * @param si the si value
55 * @return the Dimensionless instance based on an SI value
56 */
57 public static Dimensionless ofSi(final double si)
58 {
59 return new Dimensionless(si, Unitless.BASE);
60 }
61
62 @Override
63 public Dimensionless instantiateSi(final double si)
64 {
65 return ofSi(si);
66 }
67
68 @Override
69 public SIUnit siUnit()
70 {
71 return Unitless.SI_UNIT;
72 }
73
74 /**
75 * Returns a Dimensionless representation of a textual representation of a value with a unit. The String representation that
76 * can be parsed is the double value in the unit, followed by a localized or English abbreviation of the unit. Spaces are
77 * allowed, but not required, between the value and the unit.
78 * @param text the textual representation to parse into a Dimensionless
79 * @return the Scalar representation of the value in its unit
80 * @throws IllegalArgumentException when the text cannot be parsed
81 * @throws NullPointerException when the text argument is null
82 */
83 public static Dimensionless valueOf(final String text)
84 {
85 return Quantity.valueOf(text, ZERO);
86 }
87
88 /**
89 * Returns a Dimensionless based on a value and the textual representation of the unit, which can be localized.
90 * @param valueInUnit the value, expressed in the unit as given by unitString
91 * @param unitString the textual representation of the unit
92 * @return the Scalar representation of the value in its unit
93 * @throws IllegalArgumentException when the unit cannot be parsed or is incorrect
94 * @throws NullPointerException when the unitString argument is null
95 */
96 public static Dimensionless of(final double valueInUnit, final String unitString)
97 {
98 return Quantity.of(valueInUnit, unitString, ZERO);
99 }
100
101 @Override
102 public Unitless getDisplayUnit()
103 {
104 return (Unitless) super.getDisplayUnit();
105 }
106
107 /**
108 * Calculate the division of Dimensionless and Dimensionless, which results in a Dimensionless quantity.
109 * @param v quantity
110 * @return quantity as a division of Dimensionless and Dimensionless
111 */
112 public final Dimensionless divide(final Dimensionless v)
113 {
114 return new Dimensionless(this.si() / v.si(), Unitless.BASE);
115 }
116
117 /**
118 * Calculate the division of Dimensionless and Length, which results in a LinearObjectDensity scalar.
119 * @param v scalar
120 * @return scalar as a division of Dimensionless and Length
121 */
122 public final LinearObjectDensity divide(final Length v)
123 {
124 return new LinearObjectDensity(this.si() / v.si(), LinearObjectDensity.Unit.SI);
125 }
126
127 /**
128 * Calculate the division of Dimensionless and LinearObjectDensity, which results in a Length scalar.
129 * @param v scalar
130 * @return scalar as a division of Dimensionless and LinearObjectDensity
131 */
132 public final Length divide(final LinearObjectDensity v)
133 {
134 return new Length(this.si() / v.si(), Length.Unit.SI);
135 }
136
137 /**
138 * Calculate the division of Dimensionless and Duration, which results in a Frequency scalar.
139 * @param v scalar
140 * @return scalar as a division of Dimensionless and Duration
141 */
142 public final Frequency divide(final Duration v)
143 {
144 return new Frequency(this.si() / v.si(), Frequency.Unit.SI);
145 }
146
147 /**
148 * Calculate the division of Dimensionless and Frequency, which results in a Duration scalar.
149 * @param v scalar
150 * @return scalar as a division of Dimensionless and Frequency
151 */
152 public final Duration divide(final Frequency v)
153 {
154 return new Duration(this.si() / v.si(), Duration.Unit.SI);
155 }
156
157 /**
158 * Calculate the division of Dimensionless and ElectricalConductance, which results in a ElectricalResistance scalar.
159 * @param v scalar
160 * @return scalar as a division of Dimensionless and ElectricalConductance
161 */
162 public final ElectricalResistance divide(final ElectricalConductance v)
163 {
164 return new ElectricalResistance(this.si() / v.si(), ElectricalResistance.Unit.SI);
165 }
166
167 /**
168 * Calculate the division of Dimensionless and ElectricalResistance, which results in a ElectricalConductance scalar.
169 * @param v scalar
170 * @return scalar as a division of Dimensionless and ElectricalResistance
171 */
172 public final ElectricalConductance divide(final ElectricalResistance v)
173 {
174 return new ElectricalConductance(this.si() / v.si(), ElectricalConductance.Unit.SI);
175 }
176
177 @Override
178 public Dimensionless reciprocal()
179 {
180 return ofSi(1.0 / this.si());
181 }
182
183 }