Add Temperature unit, works with: Celsius, Fahrenheit, Kelvin, Rankin…

…e and Romer

CHANGELOG.md

@@ -6,8 +6,8 @@
 
 Included right now:
 
-- Speed
-- Length
+- `Speed`
+- `Length`
 
 ## 0.0.2
 
@@ -22,5 +22,9 @@ Minor update, add new tests
 
 ## 0.0.4
 
-Added Angle unit
-  Supports negative angles, not restricted to 360 degrees or 2PI radians
+Added `Angle` unit
+  Supports negative angles, not restricted to 360 degrees or 2PI radians
+
+## 0.0.5
+Added `Temperature` unit ... works with:
+  Celsius, Fahrenheit, Kelvin, Rankine and Romer

README.md

@@ -4,10 +4,12 @@ A starting point for measurement units in Dart.
 
 Included right now:
 
-- Speed
-- Length
-- Angle
+- `Speed`
+- `Length`
+- `Angle`
   Supports negative angles, not restricted to 360 degrees or 2PI radians
+- `Temperature` ... works with:
+  Celsius, Fahrenheit, Kelvin, Rankine and Romer
 
 ## Usage
 

lib/src/temperature.dart

@@ -0,0 +1,50 @@
+class Temperature implements Comparable<Temperature> {
+    /*
+   * The value of this Temperature object in celsius degrees.
+   */
+    final double _temperature;
+
+    ///celsius to fahrenheit
+    static double _celsius_to_fahrenheit(double value) => value * 9 / 5 + 32;
+    ///to/from kelvin
+    static const double _kelvin = 273.15;
+    static double _kelvin_to_celsius(double value) => value < 0 ? -_kelvin : value - _kelvin;
+
+    ///celsius to rankine
+    static double _celsius_to_rankine(double value) => value * 9 / 5 + 32 + 459.67;
+    ///celsius to romer
+    static double _celsius_to_romer(double value) => value * 21 / 40 + 7.5;
+
+    ///fahrenheit to celsius
+    static double _fahrenheit_to_celsius(double value) => (value - 32) * 5/9;
+    ///rankine to celsius
+    static double _rankine_to_celsius(double value) => value < 0 ? -_kelvin : (value - 459.67 - 32) * 5/9;
+    ///romer to celsius
+    static double _romer_to_celsius(double value) => (value - 7.5) * 40/21;
+
+    Temperature.fromCelsius({double value : 0.0}): _temperature = value;
+    Temperature.fromFahrenheit({double value : 0.0}): _temperature = _fahrenheit_to_celsius(value);
+    Temperature.fromKelvin({double value : 0.0}): _temperature = _kelvin_to_celsius(value);
+    Temperature.fromRankine({double value : 0.0}): _temperature = _rankine_to_celsius(value);
+    Temperature.fromRomer({double value : 0.0}): _temperature = _romer_to_celsius(value);
+
+
+    double get inCelsius => _returnValue(_temperature);
+    double get inFahrenheit => _returnValue(_celsius_to_fahrenheit(_temperature));
+    double get inKelvin => _returnValue(_temperature + _kelvin);
+    double get inRankine => _returnValue(_celsius_to_rankine(_temperature));
+    double get inRomer => _returnValue(_celsius_to_romer(_temperature));
+
+    double _returnValue(num value) => double.parse(value.toStringAsFixed(6));
+
+    /**
+     * Compares this Temperature to [other], returning zero if the values are equal.
+     *
+     * Returns a negative integer if this `Temperature` is shorter than
+     * [other], or a positive integer if it is longer.
+     *
+     * A negative `Temperature` is always considered shorter than a positive one.
+     *
+     */
+    int compareTo(Temperature other) => _temperature.compareTo(other._temperature);
+}

lib/units.dart

@@ -6,4 +6,5 @@ library units;
 
 export 'src/speed.dart';
 export 'src/length.dart';
-export 'src/angle.dart';
+export 'src/angle.dart';
+export 'src/temperature.dart';

pubspec.yaml

@@ -1,6 +1,6 @@
 name: units
 description: A starting point for measurement units in Dart.
-version: 0.0.4
+version: 0.0.5
 homepage: https://github.com/yeradis/units.dart
 author: Yeradis P. Barbosa Marrero <yeradis@gmail.com>
 

test/temperature_test.dart

@@ -0,0 +1,127 @@
+import 'package:units/units.dart';
+import 'package:test/test.dart';
+
+void main() {
+    group('Angle tests', () {
+        test('Having -1.0 and 0.0 celsius degree should match return', () {
+            expect(new Temperature.fromCelsius(value: -1.0).inCelsius, equals(-1.0));
+            expect(new Temperature.fromCelsius(value: -1.0).inFahrenheit, equals(30.2));
+            expect(new Temperature.fromCelsius(value: -1.0).inKelvin, equals(272.15));
+            expect(new Temperature.fromCelsius(value: -1.0).inRankine, equals(489.87));
+            expect(new Temperature.fromCelsius(value: -1.0).inRomer, equals(6.975));
+
+            expect(new Temperature.fromCelsius(value: 0.0).inCelsius, equals(0.0));
+            expect(new Temperature.fromCelsius(value: 0.0).inFahrenheit, equals(32));
+            expect(new Temperature.fromCelsius(value: 0.0).inKelvin, equals(273.15));
+            expect(new Temperature.fromCelsius(value: 0.0).inRankine, equals(491.67));
+            expect(new Temperature.fromCelsius(value: 0.0).inRomer, equals(7.5));
+        });
+
+        test('Having -273.15 celsius degress should return 0.0 kelvin and viceversa', () {
+            expect(new Temperature.fromCelsius(value: -273.15).inKelvin, equals(0.0));
+            expect(new Temperature.fromKelvin(value: 0.0).inCelsius, equals(-273.15));
+        });
+
+        test('Having -1.0 and 0.0 fahrenheit degree should match return', () {
+            expect(new Temperature.fromFahrenheit(value: -1.0).inCelsius, equals(-18.333333));
+            expect(new Temperature.fromFahrenheit(value: -1.0).inFahrenheit, equals(-1.0));
+            expect(new Temperature.fromFahrenheit(value: -1.0).inKelvin, equals(254.816667));
+            expect(new Temperature.fromFahrenheit(value: -1.0).inRankine, equals(458.67));
+            expect(new Temperature.fromFahrenheit(value: -1.0).inRomer, equals(-2.125));
+
+            expect(new Temperature.fromFahrenheit(value: 0.0).inCelsius, equals(-17.777778));
+            expect(new Temperature.fromFahrenheit(value: 0.0).inFahrenheit, equals(0.0));
+            expect(new Temperature.fromFahrenheit(value: 0.0).inKelvin, equals(255.372222));
+            expect(new Temperature.fromFahrenheit(value: 0.0).inRankine, equals(459.67));
+            expect(new Temperature.fromFahrenheit(value: 0.0).inRomer, equals(-1.833333));
+        });
+
+        test('Having -1.0 and 0.0 kelvin should match return', () {
+            expect(new Temperature.fromKelvin(value: -1.0).inCelsius, equals(-273.15));
+            expect(new Temperature.fromKelvin(value: -1.0).inFahrenheit, equals(-459.67));
+            expect(new Temperature.fromKelvin(value: -1.0).inKelvin, equals(0.0));
+            expect(new Temperature.fromKelvin(value: -1.0).inRankine, equals(0.0));
+            expect(new Temperature.fromKelvin(value: -1.0).inRomer, equals(-135.90375));
+
+            expect(new Temperature.fromKelvin(value: 0.0).inCelsius, equals(-273.15));
+            expect(new Temperature.fromKelvin(value: 0.0).inFahrenheit, equals(-459.67));
+            expect(new Temperature.fromKelvin(value: 0.0).inKelvin, equals(0.0));
+            expect(new Temperature.fromKelvin(value: 0.0).inRankine, equals(0.0));
+            expect(new Temperature.fromKelvin(value: 0.0).inRomer, equals(-135.90375));
+        });
+
+        test('Having -1.0, 0.0, 0.5 and 3.7 rankine should match return', () {
+            expect(new Temperature.fromRankine(value: -1.0).inCelsius, equals(-273.15));
+            expect(new Temperature.fromRankine(value: -1.0).inFahrenheit, equals(-459.67));
+            expect(new Temperature.fromRankine(value: -1.0).inKelvin, equals(0.0));
+            expect(new Temperature.fromRankine(value: -1.0).inRankine, equals(0.0));
+            expect(new Temperature.fromRankine(value: -1.0).inRomer, equals(-135.90375));
+
+            expect(new Temperature.fromRankine(value: 0.0).inCelsius, equals(-273.15));
+            expect(new Temperature.fromRankine(value: 0.0).inFahrenheit, equals(-459.67));
+            expect(new Temperature.fromRankine(value: 0.0).inKelvin, equals(0.0));
+            expect(new Temperature.fromRankine(value: 0.0).inRankine, equals(0.0));
+            expect(new Temperature.fromRankine(value: 0.0).inRomer, equals(-135.90375));
+
+            expect(new Temperature.fromRankine(value: 0.5).inCelsius, equals(-272.872222));
+            expect(new Temperature.fromRankine(value: 0.5).inFahrenheit, equals(-459.17));
+            expect(new Temperature.fromRankine(value: 0.5).inKelvin, equals(0.277778));
+            expect(new Temperature.fromRankine(value: 0.5).inRankine, equals(0.5));
+            expect(new Temperature.fromRankine(value: 0.5).inRomer, equals(-135.757917));
+
+            expect(new Temperature.fromRankine(value: 3.7).inCelsius, equals(-271.094444));
+            expect(new Temperature.fromRankine(value: 3.7).inFahrenheit, equals(-455.97));
+            expect(new Temperature.fromRankine(value: 3.7).inKelvin, equals(2.055556));
+            expect(new Temperature.fromRankine(value: 3.7).inRankine, equals(3.7));
+            expect(new Temperature.fromRankine(value: 3.7).inRomer, equals(-134.824583));
+        });
+    });
+
+    test('Having -1.0, 0.0, 0.5 and 3.7 rankine should match return', () {
+        expect(new Temperature.fromRomer(value: -1.0).inCelsius, equals(-16.190476));
+        expect(new Temperature.fromRomer(value: -1.0).inFahrenheit, equals(2.857143));
+        expect(new Temperature.fromRomer(value: -1.0).inKelvin, equals(256.959524));
+        expect(new Temperature.fromRomer(value: -1.0).inRankine, equals(462.527143));
+        expect(new Temperature.fromRomer(value: -1.0).inRomer, equals(-1.0));
+
+        expect(new Temperature.fromRomer(value: 0.0).inCelsius, equals(-14.285714));
+        expect(new Temperature.fromRomer(value: 0.0).inFahrenheit, equals(6.285714));
+        expect(new Temperature.fromRomer(value: 0.0).inKelvin, equals(258.864286));
+        expect(new Temperature.fromRomer(value: 0.0).inRankine, equals(465.955714));
+        expect(new Temperature.fromRomer(value: 0.0).inRomer, equals(0.0));
+
+        expect(new Temperature.fromRomer(value: 0.5).inCelsius, equals(-13.333333));
+        expect(new Temperature.fromRomer(value: 0.5).inFahrenheit, equals(8));
+        expect(new Temperature.fromRomer(value: 0.5).inKelvin, equals(259.816667));
+        expect(new Temperature.fromRomer(value: 0.5).inRankine, equals(467.67));
+        expect(new Temperature.fromRomer(value: 0.5).inRomer, equals(0.5));
+
+        expect(new Temperature.fromRomer(value: 3.7).inCelsius, equals(-7.238095));
+        expect(new Temperature.fromRomer(value: 3.7).inFahrenheit, equals(18.971429));
+        expect(new Temperature.fromRomer(value: 3.7).inKelvin, equals(265.911905));
+        expect(new Temperature.fromRomer(value: 3.7).inRankine, equals(478.641429));
+        expect(new Temperature.fromRomer(value: 3.7).inRomer, equals(3.7));
+    });
+
+    group('Temperature comparisson tests', () {
+        Temperature temperature20;
+        Temperature temperature4;
+
+        setUp(() {
+            temperature20 = new Temperature.fromCelsius(value: 20.0);
+            temperature4 = new Temperature.fromCelsius(value: 4.0);
+        });
+
+        test('Comparing same, should return 0', () {
+            expect(temperature20.compareTo(temperature20), equals(0));
+        });
+
+        test('4 is shorter than Distance 20', () {
+            expect(temperature4.compareTo(temperature20), lessThan(0));
+        });
+
+        test('20 is greater than 4', () {
+            expect(temperature20.compareTo(temperature4), greaterThan(0));
+        });
+    });
+}

test/test_all.dart

@@ -3,9 +3,11 @@ import 'package:test/test.dart';
 import 'angle_test.dart' as angle;
 import 'length_test.dart' as length;
 import 'speed_test.dart' as speed;
+import 'temperature_test.dart' as temperature;
 
 void main() {
     group('angle', angle.main);
     group('length', length.main);
     group('speed', speed.main);
+    group('temperature', temperature.main);
 }