Add formula to compute electric power

Electric power is defined as P = U * I (Power equals potential times current)
angularsen · Jun 2, 2020 · 089f858 · 089f858
1 parent 5719cb1
commit 089f858
Show file tree

Hide file tree

Showing 6 changed files with 56 additions and 0 deletions.
diff --git a/UnitsNet.Tests/CustomCode/ElectricCurrentTests.cs b/UnitsNet.Tests/CustomCode/ElectricCurrentTests.cs
@@ -34,5 +34,12 @@ public void ElectricCurrentTimesElectricResistanceEqualsElectricPotential(float
             ElectricPotential potential = ElectricCurrent.FromAmperes(current) * ElectricResistance.FromOhms(resistance);
             Assert.Equal(expected, potential.Volts);
         }
+
+        [Fact]
+        public void ElectricCurrentMultipliedByElectricPotentialEqualsPower()
+        {
+            Power p = ElectricCurrent.FromAmperes(2) * ElectricPotential.FromVolts(10);
+            Assert.Equal(20, p.Watts);
+        }
     }
 }
diff --git a/UnitsNet.Tests/CustomCode/ElectricPotentialTests.cs b/UnitsNet.Tests/CustomCode/ElectricPotentialTests.cs
@@ -40,5 +40,12 @@ public void ElectricPotentialDividedByElectricResistanceEqualsElectricCurrent(fl
             ElectricCurrent current = ElectricPotential.FromVolts(potential) / ElectricResistance.FromOhms(resistance);
             Assert.Equal(expected, current.Amperes);
         }
+
+        [Fact]
+        public void ElectricPotentialMultipliedByElectricCurrentEqualsPower()
+        {
+            Power p = ElectricPotential.FromVolts(10) * ElectricCurrent.FromAmperes(2);
+            Assert.Equal(20, p.Watts);
+        }
     }
 }
diff --git a/UnitsNet.Tests/CustomCode/PowerTests.cs b/UnitsNet.Tests/CustomCode/PowerTests.cs
@@ -127,5 +127,19 @@ public void PowerDividedBySpecificEnergyEqualsMassFlow()
             MassFlow massFlow = Power.FromWatts(15.0) / SpecificEnergy.FromJoulesPerKilogram(3);
             Assert.Equal(massFlow, MassFlow.FromKilogramsPerSecond(5));
         }
+
+        [Fact]
+        public void CurrentMultipliedByPotentialEqualsPower()
+        {
+            ElectricCurrent i = ElectricCurrent.FromAmperes(5);
+            ElectricPotential u = ElectricPotential.FromVolts(10);
+            Power p = Power.FromWatts(50);
+            Assert.Equal(p, i * u);
+            Assert.Equal(p, u * i);
+
+            // Validate the inverse is true as well
+            Assert.Equal(i, p / u);
+            Assert.Equal(u, p / i);
+        }
     }
 }
diff --git a/UnitsNet/CustomCode/Quantities/ElectricCurrent.extra.cs b/UnitsNet/CustomCode/Quantities/ElectricCurrent.extra.cs
@@ -11,5 +11,12 @@ public partial struct ElectricCurrent
         {
             return ElectricPotential.FromVolts(resistance.Ohms * current.Amperes);
         }
+
+        /// <summary>Calculate <see cref="Power"/> from <see cref="ElectricPotential"/> multiplied by <see cref="ElectricCurrent"/>.</summary>
+        /// <remarks>Electric power is defined as P = U * I.</remarks>
+        public static Power operator *(ElectricCurrent current, ElectricPotential potential)
+        {
+            return Power.FromWatts(potential.Volts * current.Amperes);
+        }
     }
 }
diff --git a/UnitsNet/CustomCode/Quantities/ElectricPotential.extra.cs b/UnitsNet/CustomCode/Quantities/ElectricPotential.extra.cs
@@ -32,5 +32,12 @@ public AmplitudeRatio ToAmplitudeRatio()
         {
             return ElectricCurrent.FromAmperes(potential.Volts / resistance.Ohms);
         }
+
+        /// <summary>Calculate <see cref="Power"/> from <see cref="ElectricPotential"/> multiplied by <see cref="ElectricCurrent"/>.</summary>
+        /// <remarks>Electric power is defined as P = U * I.</remarks>
+        public static Power operator *(ElectricPotential potential, ElectricCurrent current)
+        {
+            return Power.FromWatts(potential.Volts * current.Amperes);
+        }
     }
 }
diff --git a/UnitsNet/CustomCode/Quantities/Power.extra.cs b/UnitsNet/CustomCode/Quantities/Power.extra.cs
@@ -92,5 +92,19 @@ public PowerRatio ToPowerRatio()
         {
             return Area.FromSquareMeters( power.Watts / heatFlux.WattsPerSquareMeter );
         }
+
+        /// <summary>Calculate <see cref="ElectricCurrent"/> from <see cref="Power"/> divided by <see cref="ElectricPotential"/>.</summary>
+        /// <remarks>Electric power is defined as P = U * I, so I = P / U.</remarks>
+        public static ElectricCurrent operator /(Power power, ElectricPotential potential)
+        {
+            return ElectricCurrent.FromAmperes(power.Watts / potential.Volts);
+        }
+
+        /// <summary>Calculate <see cref="ElectricPotential"/> from <see cref="Power"/> divided by <see cref="ElectricCurrent"/>.</summary>
+        /// <remarks>Electric power is defined as P = U * I, so I = P / U.</remarks>
+        public static ElectricPotential operator /(Power power, ElectricCurrent current)
+        {
+            return ElectricPotential.FromVolts(power.Watts / current.Amperes);
+        }
     }
 }