1 package org.djunits.value.base;
2
3 import org.djunits.unit.Unit;
4 import org.djunits.value.Value;
5 import org.djutils.exceptions.Throw;
6
7 /**
8 * Scalar to distinguish a scalar from vectors and matrices.
9 * <p>
10 * Copyright (c) 2019-2024 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved. <br>
11 * BSD-style license. See <a href="https://djunits.org/docs/license.html">DJUNITS License</a>.
12 * </p>
13 * @author <a href="https://www.tudelft.nl/averbraeck" target="_blank">Alexander Verbraeck</a>
14 * @param <U> the unit
15 * @param <S> the scalar type with the given unit
16 */
17 public abstract class Scalar<U extends Unit<U>, S extends Scalar<U, S>> extends Number implements Value<U, S>, Comparable<S>
18 {
19 /** */
20 private static final long serialVersionUID = 20150626L;
21
22 /** The display unit of this AbstractScalar. */
23 private U displayUnit;
24
25 /**
26 * Construct a new Scalar.
27 * @param displayUnit U; the unit of the new AbstractScalar
28 */
29 protected Scalar(final U displayUnit)
30 {
31 Throw.whenNull(displayUnit, "display unit cannot be null");
32 this.displayUnit = displayUnit;
33 }
34
35 @Override
36 public final U getDisplayUnit()
37 {
38 return this.displayUnit;
39 }
40
41 @Override
42 public void setDisplayUnit(final U newUnit)
43 {
44 Throw.whenNull(newUnit, "newUnit may not be null");
45 this.displayUnit = newUnit;
46 }
47
48 // No hashcode or equals -- has to be implemented on a deeper level
49
50 /**
51 * Test if this DoubleScalar is less than another DoubleScalar.
52 * @param o T, a relative typed DoubleScalar; the right hand side operand of the comparison
53 * @return boolean; true if this is less than o; false otherwise
54 */
55 public abstract boolean lt(S o);
56
57 /**
58 * Test if this DoubleScalar is less than or equal to another DoubleScalar.
59 * @param o T, a relative typed DoubleScalar; the right hand side operand of the comparison
60 * @return boolean; true if this is less than or equal to o; false otherwise
61 */
62 public abstract boolean le(S o);
63
64 /**
65 * Test if this DoubleScalar is greater than another DoubleScalar.
66 * @param o T, a relative typed DoubleScalar; the right hand side operand of the comparison
67 * @return boolean; true if this is greater than o; false otherwise
68 */
69 public abstract boolean gt(S o);
70
71 /**
72 * Test if this DoubleScalar is greater than or equal to another DoubleScalar.
73 * @param o T, a relative typed DoubleScalar; the right hand side operand of the comparison
74 * @return boolean; true if this is greater than or equal to o; false otherwise
75 */
76 public abstract boolean ge(S o);
77
78 /**
79 * Test if this DoubleScalar is equal to another DoubleScalar.
80 * @param o T, a relative typed DoubleScalar; the right hand side operand of the comparison
81 * @return boolean; true if this is equal to o; false otherwise
82 */
83 public abstract boolean eq(S o);
84
85 /**
86 * Test if this DoubleScalar is not equal to another DoubleScalar.
87 * @param o T, a relative typed DoubleScalar; the right hand side operand of the comparison
88 * @return boolean; true if this is not equal to o; false otherwise
89 */
90 public abstract boolean ne(S o);
91
92 /**
93 * Test if this DoubleScalar is less than 0.0.
94 * @return boolean; true if this is less than 0.0; false if this is not less than 0.0
95 */
96 public abstract boolean lt0();
97
98 /**
99 * Test if this DoubleScalar is less than or equal to 0.0.
100 * @return boolean; true if this is less than or equal to 0.0; false if this is not less than or equal to 0.0
101 */
102 public abstract boolean le0();
103
104 /**
105 * Test if this DoubleScalar is greater than 0.0.
106 * @return boolean; true if this is greater than 0.0; false if this is not greater than 0.0
107 */
108 public abstract boolean gt0();
109
110 /**
111 * Test if this DoubleScalar is greater than or equal to 0.0.
112 * @return boolean; true if this is greater than or equal to 0.0; false if this is not greater than or equal to 0.0
113 */
114 public abstract boolean ge0();
115
116 /**
117 * Test if this DoubleScalar is equal to 0.0.
118 * @return boolean; true if this is equal to 0.0; false if this is not equal to 0.0
119 */
120 public abstract boolean eq0();
121
122 /**
123 * Test if this DoubleScalar is not equal to 0.0.
124 * @return boolean; true if this is not equal to 0.0; false if this is equal to 0.0
125 */
126 public abstract boolean ne0();
127
128 /**
129 * Concise textual representation of this value, without the engineering formatting, so without trailing zeroes. A space is
130 * added between the number and the unit.
131 * @return a String with the value with the default textual representation of the unit attached.
132 */
133 public abstract String toTextualString();
134
135 /**
136 * Concise textual representation of this value, without the engineering formatting, so without trailing zeroes. A space is
137 * added between the number and the unit.
138 * @param displayUnit U; the display unit for the value
139 * @return a String with the value with the default textual representation of the provided unit attached.
140 */
141 public abstract String toTextualString(U displayUnit);
142
143 /**
144 * Concise display description of this value, without the engineering formatting, so without trailing zeroes. A space is
145 * added between the number and the unit.
146 * @return a String with the value with the default display representation of the unit attached.
147 */
148 public abstract String toDisplayString();
149
150 /**
151 * Concise display description of this value, without the engineering formatting, so without trailing zeroes. A space is
152 * added between the number and the unit.
153 * @param displayUnit U; the display unit for the value
154 * @return a String with the value with the default display representation of the provided unit attached.
155 */
156 public abstract String toDisplayString(U displayUnit);
157
158 /**
159 * Format a string according to the current locale and the standard (minimized) format, such as "3.14" or "300.0".
160 * @param d double; the number to format
161 * @return String; the formatted number using the current Locale
162 */
163 public String format(final double d)
164 {
165 if (d < 1E-5 || d > 1E5)
166 return format(d, "%E");
167 return format(d, "%f");
168 }
169
170 /**
171 * Format a string according to the current locale and the provided format string.
172 * @param d double; the number to format
173 * @param format String; the formatting string to use for the number
174 * @return String; the formatted number using the current Locale and the format string
175 */
176 public String format(final double d, final String format)
177 {
178 String s = String.format(format, d);
179 if (s.contains("e") || s.contains("E"))
180 return s;
181 while (s.endsWith("0") && s.length() > 2)
182 s = s.substring(0, s.length() - 1);
183 String last = s.substring(s.length() - 1);
184 if (!"01234567890".contains(last))
185 s += "0";
186 return s;
187 }
188
189 }