Relative and absolute equality (#451)

This introduces relative equality checks, which makes it easier to do equality checks without knowing the values or units in advance.
It also improves the existing absolute equality checks to more intuitively use `this` as the reference value/unit instead of the base unit.

* Add `static Comparison` type for absolute and relative equality logic, that take a tolerance and a `ComparisonType`

* Add new overload for instance method `Equals()` on quantity types

* Adding ability to compare by relative and absolute values

* Fixing units and tests due to new relative tolerance

* Removing default parameters for windows runtime component

* Fixing therm(UK) values

* Relative difference calculation should be against expected value

* Make sure comparison is done to the current units of [this] to avoid uneccessary scaling

* Fix obsolete message of Equals($quantityName other, $quantityName maxError). 

* Fix Equals methods that were scaling to base units when unnecessary

Author: tmilnthorp

UnitsNet.Tests/AssertEx.cs

@@ -1,4 +1,5 @@
-using Xunit;
+using System;
+using Xunit;
 
 namespace UnitsNet.Tests
 {
@@ -7,9 +8,22 @@ namespace UnitsNet.Tests
     /// </summary>
     public static class AssertEx
     {
-        public static void EqualTolerance(double expected, double actual, double tolerance)
+        public static void EqualTolerance(double expected, double actual, double tolerance, ComparisonType comparisonType = ComparisonType.Relative)
         {
-            Assert.True(actual >= expected - tolerance && actual <= expected + tolerance, $"Values are not equal within tolerance: {tolerance}\nExpected: {expected}\nActual: {actual}\nDiff: {actual - expected:e}");
+            if(comparisonType == ComparisonType.Relative)
+            {
+                bool areEqual = UnitsNet.Comparison.EqualsRelative(expected, actual, tolerance);
+
+                double difference = Math.Abs(expected - actual);
+                double relativeDifference = difference / expected;
+
+                Assert.True( areEqual, $"Values are not equal within relative tolerance: {tolerance:P4}\nExpected: {expected}\nActual: {actual}\nDiff: {relativeDifference:P4}" );
+            }
+            else if( comparisonType == ComparisonType.Absolute )
+            {
+                bool areEqual = UnitsNet.Comparison.EqualsAbsolute(expected, actual, tolerance);
+                Assert.True( areEqual, $"Values are not equal within absolute tolerance: {tolerance}\nExpected: {expected}\nActual: {actual}\nDiff: {actual - expected:e}" );
+            }
         }
     }
 }

UnitsNet.Tests/CustomCode/AccelerationTests.cs

@@ -39,7 +39,7 @@ public class AccelerationTests : AccelerationTestsBase
 
         protected override double NanometersPerSecondSquaredInOneMeterPerSecondSquared => 1E9;
 
-        protected override double StandardGravityInOneMeterPerSecondSquared => 0.1019727;
+        protected override double StandardGravityInOneMeterPerSecondSquared => 1.019716212977928e-1;
 
         protected override double InchesPerSecondSquaredInOneMeterPerSecondSquared => 39.3700787;
 

UnitsNet.Tests/CustomCode/AngleTests.cs

@@ -52,7 +52,7 @@ public class AngleTests : AngleTestsBase
 
         protected override double ArcsecondsInOneDegree => 3600.0;
 
-        protected override double RevolutionsInOneDegree => 2.77E-3;
+        protected override double RevolutionsInOneDegree => 2.777777777777777e-3;
 
         [Fact]
         public void AngleDividedByDurationEqualsRotationalSpeed()

UnitsNet.Tests/CustomCode/DurationTests.cs

@@ -36,19 +36,19 @@ public class DurationTests : DurationTestsBase
 
         protected override double MinutesInOneSecond => 0.0166667;
 
-        protected override double MonthsInOneSecond => 3.8027e-7;
+        protected override double MonthsInOneSecond => 3.858024691358024e-7;
 
-        protected override double Months30InOneSecond => 3.85802469135e-7;
+        protected override double Months30InOneSecond => 3.858024691358024e-7;
 
         protected override double NanosecondsInOneSecond => 1e+9;
 
         protected override double SecondsInOneSecond => 1;
 
-        protected override double WeeksInOneSecond => 1.6534e-6;
+        protected override double WeeksInOneSecond => 1.653439153439153e-6;
 
-        protected override double YearsInOneSecond => 3.1689e-8;
+        protected override double YearsInOneSecond => 3.170979198376458e-8;
 
-        protected override double Years365InOneSecond => 3.170979198376e-8;
+        protected override double Years365InOneSecond => 3.170979198376458e-8;
 
         [Fact]
         public static void ToTimeSpanShouldThrowExceptionOnValuesLargerThanTimeSpanMax()

UnitsNet.Tests/CustomCode/EnergyTests.cs

@@ -24,7 +24,7 @@ namespace UnitsNet.Tests.CustomCode
     public class EnergyTests : EnergyTestsBase
     {
         // TODO Override properties in base class here
-        protected override double ThermsImperialInOneJoule => 9.478171203551087813109937767482e-15;
+        protected override double ThermsImperialInOneJoule => 9.478171203551087813109937767482e-9;
 
         protected override double JoulesInOneJoule => 1;
 
@@ -40,11 +40,11 @@ public class EnergyTests : EnergyTestsBase
 
         protected override double CaloriesInOneJoule => 0.239005736;
 
-        protected override double DecathermsEcInOneJoule => 9.47816988e-10;
+        protected override double DecathermsEcInOneJoule => 9.478171203133172e-10;
 
-        protected override double DecathermsImperialInOneJoule => 9.478171203551087813109937767482e-15;
+        protected override double DecathermsImperialInOneJoule => 9.478171203551087813109937767482e-10;
 
-        protected override double DecathermsUsInOneJoule => 9.4804342797334860315281322406817e-10;
+        protected override double DecathermsUsInOneJoule => 9.480434279733486e-10;
 
         protected override double ElectronVoltsInOneJoule => 6.241509343260179e18;
 
@@ -68,4 +68,4 @@ public class EnergyTests : EnergyTestsBase
 
         protected override double WattHoursInOneJoule => 0.000277777778;
     }
-}
+}

UnitsNet.Tests/CustomCode/ForceTests.cs

@@ -41,7 +41,7 @@ public class ForceTests : ForceTestsBase
 
         protected override double PoundsForceInOneNewton => 0.22481;
 
-        protected override double TonnesForceInOneNewton => 1.02e-4;
+        protected override double TonnesForceInOneNewton => 1.019716212977928e-4;
 
         [Fact]
         public void ForceDividedByAreaEqualsPressure()

UnitsNet.Tests/CustomCode/IrradiationTests.cs

@@ -48,8 +48,8 @@ public class IrradiationTests : IrradiationTestsBase
     {
         protected override double JoulesPerSquareMeterInOneJoulePerSquareMeter => 1;
 
-        protected override double WattHoursPerSquareMeterInOneJoulePerSquareMeter => 2.78E-04;
+        protected override double WattHoursPerSquareMeterInOneJoulePerSquareMeter => 2.777777777777778e-4;
 
-        protected override double KilowattHoursPerSquareMeterInOneJoulePerSquareMeter => 2.78E-07;
+        protected override double KilowattHoursPerSquareMeterInOneJoulePerSquareMeter => 2.777777777777778e-7;
     }
 }

UnitsNet.Tests/CustomCode/MassTests.cs

@@ -42,11 +42,11 @@ public class MassTests : MassTestsBase
 
         protected override double KilotonnesInOneKilogram => 1E-6;
 
-        protected override double LongTonsInOneKilogram => 0.000984207;
+        protected override double LongTonsInOneKilogram => 9.842065276110606e-4;
 
         protected override double MegapoundsInOneKilogram => 2.2046226218487757e-6;
 
-        protected override double MegatonnesInOneKilogram => 1E-6;
+        protected override double MegatonnesInOneKilogram => 1E-9;
 
         protected override double MicrogramsInOneKilogram => 1E9;
 
@@ -60,7 +60,7 @@ public class MassTests : MassTestsBase
 
         protected override double PoundsInOneKilogram => 2.2046226218487757d;
 
-        protected override double ShortTonsInOneKilogram => 0.00110231;
+        protected override double ShortTonsInOneKilogram => 1.102311310924388e-3;
 
         protected override double StoneInOneKilogram => 0.1574731728702698;
 
@@ -105,4 +105,4 @@ public void MassTimesAccelerationEqualsForce()
             Assert.Equal(force, Force.FromNewtons(54));
         }
     }
-}
+}

UnitsNet.Tests/CustomCode/PressureTests.cs

@@ -30,11 +30,11 @@ public class PressureTests : PressureTestsBase
 
         protected override double BarsInOnePascal => 1E-5;
 
-        protected override double KilogramsForcePerSquareCentimeterInOnePascal => 0.101971621e-5;
+        protected override double KilogramsForcePerSquareCentimeterInOnePascal => 1.019716212977928e-5;
 
         protected override double KilogramsForcePerSquareMeterInOnePascal => 0.101971621;
 
-        protected override double KilogramsForcePerSquareMillimeterInOnePascal => 0.101971621e-7;
+        protected override double KilogramsForcePerSquareMillimeterInOnePascal => 1.019716212977928e-7;
 
         protected override double KilonewtonsPerSquareCentimeterInOnePascal => 1e-7;
 
@@ -44,9 +44,9 @@ public class PressureTests : PressureTestsBase
 
         protected override double KilopascalsInOnePascal => 1e-3;
 
-        protected override double KilopoundsForcePerSquareFootInOnePascal => 2.089e-5;
+        protected override double KilopoundsForcePerSquareFootInOnePascal => 2.088543423315013e-5;
 
-        protected override double KilopoundsForcePerSquareInchInOnePascal => 1.45e-7;
+        protected override double KilopoundsForcePerSquareInchInOnePascal => 1.450377377302092e-7;
 
         protected override double MegapascalsInOnePascal => 1E-6;
 
@@ -64,17 +64,17 @@ public class PressureTests : PressureTestsBase
 
         protected override double PoundsForcePerSquareFootInOnePascal => 0.0208854342;
 
-        protected override double PoundsForcePerSquareInchInOnePascal => 0.000145037737730209;
+        protected override double PoundsForcePerSquareInchInOnePascal => 1.450377377302092e-4;
 
-        protected override double PsiInOnePascal => 1.450377*1E-4;
+        protected override double PsiInOnePascal => 1.450377377302092e-4;
 
         protected override double TechnicalAtmospheresInOnePascal => 1.0197*1E-5;
 
-        protected override double TonnesForcePerSquareCentimeterInOnePascal => 1e-8;
+        protected override double TonnesForcePerSquareCentimeterInOnePascal => 1.019716212977928e-8;
 
-        protected override double TonnesForcePerSquareMeterInOnePascal => 1e-4;
+        protected override double TonnesForcePerSquareMeterInOnePascal => 1.019716212977928e-4;
 
-        protected override double TonnesForcePerSquareMillimeterInOnePascal => 1e-10;
+        protected override double TonnesForcePerSquareMillimeterInOnePascal => 1.019716212977928e-10;
 
         protected override double TorrsInOnePascal => 7.5006*1E-3;
 

UnitsNet.Tests/CustomCode/SpecificWeightTests.cs

@@ -25,37 +25,37 @@ namespace UnitsNet.Tests.CustomCode
 {
     public class SpecificWeightTests : SpecificWeightTestsBase
     {
-        protected override double KilogramsForcePerCubicCentimeterInOneNewtonPerCubicMeter => 0.101971621e-7;
+        protected override double KilogramsForcePerCubicCentimeterInOneNewtonPerCubicMeter => 1.019716212977928e-7;
 
         protected override double KilogramsForcePerCubicMeterInOneNewtonPerCubicMeter => 0.101971621;
 
-        protected override double KilogramsForcePerCubicMillimeterInOneNewtonPerCubicMeter => 0.101971621e-10;
+        protected override double KilogramsForcePerCubicMillimeterInOneNewtonPerCubicMeter => 1.019716212977928e-10;
 
         protected override double KilonewtonsPerCubicCentimeterInOneNewtonPerCubicMeter => 1e-9;
 
         protected override double KilonewtonsPerCubicMeterInOneNewtonPerCubicMeter => 1e-3;
 
         protected override double KilonewtonsPerCubicMillimeterInOneNewtonPerCubicMeter => 1e-12;
 
-        protected override double KilopoundsForcePerCubicFootInOneNewtonPerCubicMeter => 6.366e-6;
+        protected override double KilopoundsForcePerCubicFootInOneNewtonPerCubicMeter => 6.365880354264159e-6;
 
-        protected override double KilopoundsForcePerCubicInchInOneNewtonPerCubicMeter => 3.684e-9;
+        protected override double KilopoundsForcePerCubicInchInOneNewtonPerCubicMeter => 3.683958538347314e-9;
 
         protected override double NewtonsPerCubicCentimeterInOneNewtonPerCubicMeter => 1e-6;
 
         protected override double NewtonsPerCubicMeterInOneNewtonPerCubicMeter => 1;
 
         protected override double NewtonsPerCubicMillimeterInOneNewtonPerCubicMeter => 1e-9;
 
-        protected override double PoundsForcePerCubicFootInOneNewtonPerCubicMeter => 0.006366;
+        protected override double PoundsForcePerCubicFootInOneNewtonPerCubicMeter => 6.365880354264159e-3;
 
-        protected override double PoundsForcePerCubicInchInOneNewtonPerCubicMeter => 3.684e-6;
+        protected override double PoundsForcePerCubicInchInOneNewtonPerCubicMeter => 3.683958538347314e-6;
 
-        protected override double TonnesForcePerCubicCentimeterInOneNewtonPerCubicMeter => 1.02e-13;
+        protected override double TonnesForcePerCubicCentimeterInOneNewtonPerCubicMeter => 1.019716212977928e-10;
 
-        protected override double TonnesForcePerCubicMeterInOneNewtonPerCubicMeter => 1.02e-4;
+        protected override double TonnesForcePerCubicMeterInOneNewtonPerCubicMeter => 1.019716212977928e-4;
 
-        protected override double TonnesForcePerCubicMillimeterInOneNewtonPerCubicMeter => 1.02e-10;
+        protected override double TonnesForcePerCubicMillimeterInOneNewtonPerCubicMeter => 1.019716212977928e-13;
 
         protected override double MeganewtonsPerCubicMeterInOneNewtonPerCubicMeter => 1e-6;
 

UnitsNet.Tests/CustomCode/TorqueTests.cs

@@ -43,13 +43,13 @@ public class TorqueTests : TorqueTestsBase
 
         protected override double KilonewtonMillimetersInOneNewtonMeter => 1;
 
-        protected override double MegapoundForceFeetInOneNewtonMeter => 7.376e-7;
+        protected override double MegapoundForceFeetInOneNewtonMeter => 7.375621492772654e-7;
 
-        protected override double KilopoundForceFeetInOneNewtonMeter => 7.376e-4;
+        protected override double KilopoundForceFeetInOneNewtonMeter => 7.375621492772654e-4;
 
-        protected override double MegapoundForceInchesInOneNewtonMeter => 8.8516E-6;
+        protected override double MegapoundForceInchesInOneNewtonMeter => 8.850745791327184e-6;
 
-        protected override double KilopoundForceInchesInOneNewtonMeter => 8.8516E-3;
+        protected override double KilopoundForceInchesInOneNewtonMeter => 8.850745791327184e-3;
 
         protected override double NewtonCentimetersInOneNewtonMeter => 100;
 
@@ -81,4 +81,4 @@ public void TorqueDividedByLengthEqualsForce()
             Assert.Equal(force, Force.FromNewtons(2));
         }
     }
-}
+}

UnitsNet.Tests/CustomCode/VolumeTests.cs

@@ -40,7 +40,7 @@ public class VolumeTests : VolumeTestsBase
 
         protected override double CubicMetersInOneCubicMeter => 1;
 
-        protected override double CubicMilesInOneCubicMeter => 3.86102*1E-7;
+        protected override double CubicMilesInOneCubicMeter => 2.399127585789277e-10;
 
         protected override double CubicMillimetersInOneCubicMeter => 1E9;
 

UnitsNet.Tests/QuantityTests.ToString.cs

@@ -28,7 +28,7 @@ namespace UnitsNet.Tests
     [Collection(nameof(UnitSystemFixture))]
     public partial class QuantityTests
     {
-        public class ToString
+        public class ToStringTests
         {
             [Fact]
             public void CreatedByDefaultCtor_ReturnsValueInBaseUnit()