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Add Lerp to IFloatingPointIeee754 (#81186)
* Add Lerp to IFloatingPointIeee754 * Add tests covering Lerp * Fix build error * Handle negative zero
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11 files changed

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11 files changed

+220
-0
lines changed

‎src/libraries/System.Private.CoreLib/src/System/Double.cs

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@@ -832,6 +832,9 @@ bool IFloatingPoint<double>.TryWriteSignificandLittleEndian(Span<byte> destinati
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/// <inheritdoc cref="IFloatingPointIeee754{TSelf}.ILogB(TSelf)" />
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public static int ILogB(double x) => Math.ILogB(x);
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/// <inheritdoc cref="IFloatingPointIeee754{TSelf}.Lerp(TSelf, TSelf, TSelf)" />
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public static double Lerp(double value1, double value2, double amount) => (value1 * (1.0 - amount)) + (value2 * amount);
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/// <inheritdoc cref="IFloatingPointIeee754{TSelf}.ReciprocalEstimate(TSelf)" />
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public static double ReciprocalEstimate(double x) => Math.ReciprocalEstimate(x);
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‎src/libraries/System.Private.CoreLib/src/System/Half.cs

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@@ -1321,6 +1321,9 @@ public static Half BitIncrement(Half x)
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/// <inheritdoc cref="IFloatingPointIeee754{TSelf}.ILogB(TSelf)" />
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public static int ILogB(Half x) => MathF.ILogB((float)x);
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/// <inheritdoc cref="IFloatingPointIeee754{TSelf}.Lerp(TSelf, TSelf, TSelf)" />
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public static Half Lerp(Half value1, Half value2, Half amount) => (Half)float.Lerp((float)value1, (float)value2, (float)amount);
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/// <inheritdoc cref="IFloatingPointIeee754{TSelf}.ReciprocalEstimate(TSelf)" />
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public static Half ReciprocalEstimate(Half x) => (Half)MathF.ReciprocalEstimate((float)x);
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‎src/libraries/System.Private.CoreLib/src/System/Numerics/IFloatingPointIeee754.cs

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@@ -72,6 +72,14 @@ public interface IFloatingPointIeee754<TSelf>
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/// <returns>The integer logarithm of <paramref name="x" />.</returns>
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static abstract int ILogB(TSelf x);
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/// <summary>Performs a linear interpolation between two values based on the given weight.</summary>
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/// <param name="value1">The first value, which is intended to be the lower bound.</param>
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/// <param name="value2">The second value, which is intended to be the upper bound.</param>
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/// <param name="amount">A value, intended to be between 0 and 1, that indicates the weight of the interpolation.</param>
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/// <returns>The interpolated value.</returns>
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/// <remarks>This method presumes inputs are well formed and does not validate that <c>value1 &lt; value2</c> nor that <c>0 &lt;= amount &lt;= 1</c>.</remarks>
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static virtual TSelf Lerp(TSelf value1, TSelf value2, TSelf amount) => (value1 * (TSelf.One - amount)) + (value2 * amount);
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/// <summary>Computes an estimate of the reciprocal of a value.</summary>
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/// <param name="x">The value whose estimate of the reciprocal is to be computed.</param>
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/// <returns>An estimate of the reciprocal of <paramref name="x" />.</returns>

‎src/libraries/System.Private.CoreLib/src/System/Runtime/InteropServices/NFloat.cs

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@@ -1164,6 +1164,9 @@ bool IFloatingPoint<NFloat>.TryWriteSignificandLittleEndian(Span<byte> destinati
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/// <inheritdoc cref="IFloatingPointIeee754{TSelf}.ILogB(TSelf)" />
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public static int ILogB(NFloat x) => NativeType.ILogB(x._value);
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/// <inheritdoc cref="IFloatingPointIeee754{TSelf}.Lerp(TSelf, TSelf, TSelf)" />
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public static NFloat Lerp(NFloat value1, NFloat value2, NFloat amount) => new NFloat(NativeType.Lerp(value1._value, value2._value, amount._value));
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/// <inheritdoc cref="IFloatingPointIeee754{TSelf}.ReciprocalEstimate(TSelf)" />
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public static NFloat ReciprocalEstimate(NFloat x) => new NFloat(NativeType.ReciprocalEstimate(x._value));
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‎src/libraries/System.Private.CoreLib/src/System/Single.cs

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@@ -812,6 +812,9 @@ bool IFloatingPoint<float>.TryWriteSignificandLittleEndian(Span<byte> destinatio
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/// <inheritdoc cref="IFloatingPointIeee754{TSelf}.ILogB(TSelf)" />
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public static int ILogB(float x) => MathF.ILogB(x);
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/// <inheritdoc cref="IFloatingPointIeee754{TSelf}.Lerp(TSelf, TSelf, TSelf)" />
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public static float Lerp(float value1, float value2, float amount) => (value1 * (1.0f - amount)) + (value2 * amount);
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/// <inheritdoc cref="IFloatingPointIeee754{TSelf}.ReciprocalEstimate(TSelf)" />
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public static float ReciprocalEstimate(float x) => MathF.ReciprocalEstimate(x);
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‎src/libraries/System.Runtime.InteropServices/ref/System.Runtime.InteropServices.cs

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@@ -1175,6 +1175,7 @@ public static void Free(void* ptr) { }
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public static bool IsPow2(System.Runtime.InteropServices.NFloat value) { throw null; }
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public static bool IsRealNumber(System.Runtime.InteropServices.NFloat value) { throw null; }
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public static bool IsSubnormal(System.Runtime.InteropServices.NFloat value) { throw null; }
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public static System.Runtime.InteropServices.NFloat Lerp(System.Runtime.InteropServices.NFloat value1, System.Runtime.InteropServices.NFloat value2, System.Runtime.InteropServices.NFloat amount) { throw null; }
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public static System.Runtime.InteropServices.NFloat Log(System.Runtime.InteropServices.NFloat x) { throw null; }
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public static System.Runtime.InteropServices.NFloat Log(System.Runtime.InteropServices.NFloat x, System.Runtime.InteropServices.NFloat newBase) { throw null; }
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public static System.Runtime.InteropServices.NFloat Log10(System.Runtime.InteropServices.NFloat x) { throw null; }

‎src/libraries/System.Runtime.InteropServices/tests/System.Runtime.InteropServices.UnitTests/System/Runtime/InteropServices/NFloatTests.cs

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@@ -2469,5 +2469,81 @@ public static void TanPiTest64(double value, double expectedResult, double allow
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AssertExtensions.Equal(-expectedResult, NFloat.TanPi((NFloat)(-value)), allowedVariance);
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AssertExtensions.Equal(+expectedResult, NFloat.TanPi((NFloat)(+value)), allowedVariance);
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}
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[ConditionalTheory(typeof(PlatformDetection), nameof(PlatformDetection.Is32BitProcess))]
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[InlineData(float.NegativeInfinity, float.NegativeInfinity, 0.5f, float.NegativeInfinity)]
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[InlineData(float.NegativeInfinity, float.NaN, 0.5f, float.NaN)]
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[InlineData(float.NegativeInfinity, float.PositiveInfinity, 0.5f, float.NaN)]
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[InlineData(float.NegativeInfinity, 0.0f, 0.5f, float.NegativeInfinity)]
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[InlineData(float.NegativeInfinity, 1.0f, 0.5f, float.NegativeInfinity)]
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[InlineData(float.NaN, float.NegativeInfinity, 0.5f, float.NaN)]
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[InlineData(float.NaN, float.NaN, 0.5f, float.NaN)]
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[InlineData(float.NaN, float.PositiveInfinity, 0.5f, float.NaN)]
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[InlineData(float.NaN, 0.0f, 0.5f, float.NaN)]
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[InlineData(float.NaN, 1.0f, 0.5f, float.NaN)]
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[InlineData(float.PositiveInfinity, float.NegativeInfinity, 0.5f, float.NaN)]
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[InlineData(float.PositiveInfinity, float.NaN, 0.5f, float.NaN)]
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[InlineData(float.PositiveInfinity, float.PositiveInfinity, 0.5f, float.PositiveInfinity)]
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[InlineData(float.PositiveInfinity, 0.0f, 0.5f, float.PositiveInfinity)]
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[InlineData(float.PositiveInfinity, 1.0f, 0.5f, float.PositiveInfinity)]
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[InlineData(1.0f, 3.0f, 0.0f, 1.0f)]
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[InlineData(1.0f, 3.0f, 0.5f, 2.0f)]
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[InlineData(1.0f, 3.0f, 1.0f, 3.0f)]
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[InlineData(1.0f, 3.0f, 2.0f, 5.0f)]
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[InlineData(2.0f, 4.0f, 0.0f, 2.0f)]
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[InlineData(2.0f, 4.0f, 0.5f, 3.0f)]
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[InlineData(2.0f, 4.0f, 1.0f, 4.0f)]
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[InlineData(2.0f, 4.0f, 2.0f, 6.0f)]
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[InlineData(3.0f, 1.0f, 0.0f, 3.0f)]
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[InlineData(3.0f, 1.0f, 0.5f, 2.0f)]
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[InlineData(3.0f, 1.0f, 1.0f, 1.0f)]
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[InlineData(3.0f, 1.0f, 2.0f, -1.0f)]
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[InlineData(4.0f, 2.0f, 0.0f, 4.0f)]
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[InlineData(4.0f, 2.0f, 0.5f, 3.0f)]
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[InlineData(4.0f, 2.0f, 1.0f, 2.0f)]
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[InlineData(4.0f, 2.0f, 2.0f, 0.0f)]
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public static void LerpTest32(float value1, float value2, float amount, float expectedResult)
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{
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AssertExtensions.Equal(+expectedResult, (float)NFloat.Lerp(+value1, +value2, amount), 0);
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AssertExtensions.Equal((expectedResult == 0.0f) ? expectedResult : -expectedResult, (float)NFloat.Lerp(-value1, -value2, amount), 0);
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}
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[ConditionalTheory(typeof(PlatformDetection), nameof(PlatformDetection.Is64BitProcess))]
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[InlineData(double.NegativeInfinity, double.NegativeInfinity, 0.5, double.NegativeInfinity)]
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[InlineData(double.NegativeInfinity, double.NaN, 0.5, double.NaN)]
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[InlineData(double.NegativeInfinity, double.PositiveInfinity, 0.5, double.NaN)]
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[InlineData(double.NegativeInfinity, 0.0, 0.5, double.NegativeInfinity)]
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[InlineData(double.NegativeInfinity, 1.0, 0.5, double.NegativeInfinity)]
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[InlineData(double.NaN, double.NegativeInfinity, 0.5, double.NaN)]
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[InlineData(double.NaN, double.NaN, 0.5, double.NaN)]
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[InlineData(double.NaN, double.PositiveInfinity, 0.5, double.NaN)]
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[InlineData(double.NaN, 0.0, 0.5, double.NaN)]
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[InlineData(double.NaN, 1.0, 0.5, double.NaN)]
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[InlineData(double.PositiveInfinity, double.NegativeInfinity, 0.5, double.NaN)]
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[InlineData(double.PositiveInfinity, double.NaN, 0.5, double.NaN)]
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[InlineData(double.PositiveInfinity, double.PositiveInfinity, 0.5, double.PositiveInfinity)]
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[InlineData(double.PositiveInfinity, 0.0, 0.5, double.PositiveInfinity)]
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[InlineData(double.PositiveInfinity, 1.0, 0.5, double.PositiveInfinity)]
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[InlineData(1.0, 3.0, 0.0, 1.0)]
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[InlineData(1.0, 3.0, 0.5, 2.0)]
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[InlineData(1.0, 3.0, 1.0, 3.0)]
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[InlineData(1.0, 3.0, 2.0, 5.0)]
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[InlineData(2.0, 4.0, 0.0, 2.0)]
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[InlineData(2.0, 4.0, 0.5, 3.0)]
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[InlineData(2.0, 4.0, 1.0, 4.0)]
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[InlineData(2.0, 4.0, 2.0, 6.0)]
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[InlineData(3.0, 1.0, 0.0, 3.0)]
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[InlineData(3.0, 1.0, 0.5, 2.0)]
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[InlineData(3.0, 1.0, 1.0, 1.0)]
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[InlineData(3.0, 1.0, 2.0, -1.0)]
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[InlineData(4.0, 2.0, 0.0, 4.0)]
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[InlineData(4.0, 2.0, 0.5, 3.0)]
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[InlineData(4.0, 2.0, 1.0, 2.0)]
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[InlineData(4.0, 2.0, 2.0, 0.0)]
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public static void LerpTest64(double value1, double value2, double amount, double expectedResult)
2544+
{
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AssertExtensions.Equal(+expectedResult, NFloat.Lerp((NFloat)(+value1), (NFloat)(+value2), (NFloat)(amount)), 0);
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AssertExtensions.Equal((expectedResult == 0.0) ? expectedResult : -expectedResult, NFloat.Lerp((NFloat)(-value1), (NFloat)(-value2), (NFloat)(amount)), 0);
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}
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}
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}

‎src/libraries/System.Runtime/ref/System.Runtime.cs

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@@ -2204,6 +2204,7 @@ public DivideByZeroException(string? message, System.Exception? innerException)
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public static bool IsPow2(double value) { throw null; }
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public static bool IsRealNumber(double value) { throw null; }
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public static bool IsSubnormal(double d) { throw null; }
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public static double Lerp(double value1, double value2, double amount) { throw null; }
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public static double Log(double x) { throw null; }
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public static double Log(double x, double newBase) { throw null; }
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public static double Log10(double x) { throw null; }
@@ -2801,6 +2802,7 @@ public enum GCNotificationStatus
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public static bool IsPow2(System.Half value) { throw null; }
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public static bool IsRealNumber(System.Half value) { throw null; }
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public static bool IsSubnormal(System.Half value) { throw null; }
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public static System.Half Lerp(System.Half value1, System.Half value2, System.Half amount) { throw null; }
28042806
public static System.Half Log(System.Half x) { throw null; }
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public static System.Half Log(System.Half x, System.Half newBase) { throw null; }
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public static System.Half Log10(System.Half x) { throw null; }
@@ -4809,6 +4811,7 @@ public SerializableAttribute() { }
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public static bool IsPow2(float value) { throw null; }
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public static bool IsRealNumber(float value) { throw null; }
48114813
public static bool IsSubnormal(float f) { throw null; }
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public static float Lerp(float value1, float value2, float amount) { throw null; }
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public static float Log(float x) { throw null; }
48134816
public static float Log(float x, float newBase) { throw null; }
48144817
public static float Log10(float x) { throw null; }
@@ -10383,6 +10386,7 @@ public partial interface IFloatingPointIeee754<TSelf> : System.IComparable, Syst
1038310386
static abstract TSelf FusedMultiplyAdd(TSelf left, TSelf right, TSelf addend);
1038410387
static abstract TSelf Ieee754Remainder(TSelf left, TSelf right);
1038510388
static abstract int ILogB(TSelf x);
10389+
static virtual TSelf Lerp(TSelf value1, TSelf value2, TSelf amount) { throw null; }
1038610390
static virtual TSelf ReciprocalEstimate(TSelf x) { throw null; }
1038710391
static virtual TSelf ReciprocalSqrtEstimate(TSelf x) { throw null; }
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static abstract TSelf ScaleB(TSelf x, int n);

‎src/libraries/System.Runtime/tests/System/DoubleTests.cs

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@@ -1617,5 +1617,43 @@ public static void TanPiTest(double value, double expectedResult, double allowed
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AssertExtensions.Equal(-expectedResult, double.TanPi(-value), allowedVariance);
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AssertExtensions.Equal(+expectedResult, double.TanPi(+value), allowedVariance);
16191619
}
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[Theory]
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[InlineData(double.NegativeInfinity, double.NegativeInfinity, 0.5, double.NegativeInfinity)]
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[InlineData(double.NegativeInfinity, double.NaN, 0.5, double.NaN)]
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[InlineData(double.NegativeInfinity, double.PositiveInfinity, 0.5, double.NaN)]
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[InlineData(double.NegativeInfinity, 0.0, 0.5, double.NegativeInfinity)]
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[InlineData(double.NegativeInfinity, 1.0, 0.5, double.NegativeInfinity)]
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[InlineData(double.NaN, double.NegativeInfinity, 0.5, double.NaN)]
1628+
[InlineData(double.NaN, double.NaN, 0.5, double.NaN)]
1629+
[InlineData(double.NaN, double.PositiveInfinity, 0.5, double.NaN)]
1630+
[InlineData(double.NaN, 0.0, 0.5, double.NaN)]
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[InlineData(double.NaN, 1.0, 0.5, double.NaN)]
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[InlineData(double.PositiveInfinity, double.NegativeInfinity, 0.5, double.NaN)]
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[InlineData(double.PositiveInfinity, double.NaN, 0.5, double.NaN)]
1634+
[InlineData(double.PositiveInfinity, double.PositiveInfinity, 0.5, double.PositiveInfinity)]
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[InlineData(double.PositiveInfinity, 0.0, 0.5, double.PositiveInfinity)]
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[InlineData(double.PositiveInfinity, 1.0, 0.5, double.PositiveInfinity)]
1637+
[InlineData(1.0, 3.0, 0.0, 1.0)]
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[InlineData(1.0, 3.0, 0.5, 2.0)]
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[InlineData(1.0, 3.0, 1.0, 3.0)]
1640+
[InlineData(1.0, 3.0, 2.0, 5.0)]
1641+
[InlineData(2.0, 4.0, 0.0, 2.0)]
1642+
[InlineData(2.0, 4.0, 0.5, 3.0)]
1643+
[InlineData(2.0, 4.0, 1.0, 4.0)]
1644+
[InlineData(2.0, 4.0, 2.0, 6.0)]
1645+
[InlineData(3.0, 1.0, 0.0, 3.0)]
1646+
[InlineData(3.0, 1.0, 0.5, 2.0)]
1647+
[InlineData(3.0, 1.0, 1.0, 1.0)]
1648+
[InlineData(3.0, 1.0, 2.0, -1.0)]
1649+
[InlineData(4.0, 2.0, 0.0, 4.0)]
1650+
[InlineData(4.0, 2.0, 0.5, 3.0)]
1651+
[InlineData(4.0, 2.0, 1.0, 2.0)]
1652+
[InlineData(4.0, 2.0, 2.0, 0.0)]
1653+
public static void LerpTest(double value1, double value2, double amount, double expectedResult)
1654+
{
1655+
AssertExtensions.Equal(+expectedResult, double.Lerp(+value1, +value2, amount), 0);
1656+
AssertExtensions.Equal((expectedResult == 0.0) ? expectedResult : -expectedResult, double.Lerp(-value1, -value2, amount), 0);
1657+
}
16201658
}
16211659
}

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