Use Math.SinCos and Math.Exp in Complex (dotnet#104313)

jozkee · Jul 3, 2024 · 8abea3a · 8abea3a
1 parent 58b5a6c
commit 8abea3a
Showing 1 changed file with 14 additions and 12 deletions.
diff --git a/src/libraries/System.Runtime.Numerics/src/System/Numerics/Complex.cs b/src/libraries/System.Runtime.Numerics/src/System/Numerics/Complex.cs
@@ -65,7 +65,8 @@ public Complex(double real, double imaginary)
 
  public static Complex FromPolarCoordinates(double magnitude, double phase)
  {
- return new Complex(magnitude * Math.Cos(phase), magnitude * Math.Sin(phase));
+ (double sin, double cos) = Math.SinCos(phase);
+ return new Complex(magnitude * cos, magnitude * sin);
  }
 
  public static Complex Negate(Complex value)
@@ -414,7 +415,8 @@ public string ToString([StringSyntax(StringSyntaxAttribute.NumericFormat)] strin
 
  public static Complex Sin(Complex value)
  {
- return new Complex(Math.Sin(value.m_real) * Math.Cosh(value.m_imaginary), Math.Cos(value.m_real) * Math.Sinh(value.m_imaginary));
+ (double sin, double cos) = Math.SinCos(value.m_real);
+ return new Complex(sin * Math.Cosh(value.m_imaginary), cos * Math.Sinh(value.m_imaginary));
  // There is a known limitation with this algorithm: inputs that cause sinh and cosh to overflow, but for
  // which sin or cos are small enough that sin * cosh or cos * sinh are still representable, nonetheless
  // produce overflow. For example, Sin((0.01, 711.0)) should produce (~3.0E306, PositiveInfinity), but
@@ -451,7 +453,8 @@ public static Complex Asin(Complex value)
 
  public static Complex Cos(Complex value)
  {
- return new Complex(Math.Cos(value.m_real) * Math.Cosh(value.m_imaginary), -Math.Sin(value.m_real) * Math.Sinh(value.m_imaginary));
+ (double sin, double cos) = Math.SinCos(value.m_real);
+ return new Complex(cos * Math.Cosh(value.m_imaginary), -sin * Math.Sinh(value.m_imaginary));
  }
 
  public static Complex Cosh(Complex value)
@@ -494,16 +497,17 @@ public static Complex Tan(Complex value)
 
  double x2 = 2.0 * value.m_real;
  double y2 = 2.0 * value.m_imaginary;
+ (double sin, double cos) = Math.SinCos(x2);
  double cosh = Math.Cosh(y2);
  if (Math.Abs(value.m_imaginary) <= 4.0)
  {
- double D = Math.Cos(x2) + cosh;
- return new Complex(Math.Sin(x2) / D, Math.Sinh(y2) / D);
+ double D = cos + cosh;
+ return new Complex(sin / D, Math.Sinh(y2) / D);
  }
  else
  {
- double D = 1.0 + Math.Cos(x2) / cosh;
- return new Complex(Math.Sin(x2) / cosh / D, Math.Tanh(y2) / D);
+ double D = 1.0 + cos / cosh;
+ return new Complex(sin / cosh / D, Math.Tanh(y2) / D);
  }
  }
 
@@ -663,9 +667,7 @@ public static Complex Log10(Complex value)
  public static Complex Exp(Complex value)
  {
  double expReal = Math.Exp(value.m_real);
- double cosImaginary = expReal * Math.Cos(value.m_imaginary);
- double sinImaginary = expReal * Math.Sin(value.m_imaginary);
- return new Complex(cosImaginary, sinImaginary);
+ return FromPolarCoordinates(expReal, value.m_imaginary);
  }
 
  public static Complex Sqrt(Complex value)
@@ -770,9 +772,9 @@ public static Complex Pow(Complex value, Complex power)
  double theta = Math.Atan2(valueImaginary, valueReal);
  double newRho = powerReal * theta + powerImaginary * Math.Log(rho);
 
- double t = Math.Pow(rho, powerReal) * Math.Pow(Math.E, -powerImaginary * theta);
+ double t = Math.Pow(rho, powerReal) * Math.Exp(-powerImaginary * theta);
 
- return new Complex(t * Math.Cos(newRho), t * Math.Sin(newRho));
+ return FromPolarCoordinates(t, newRho);
  }
 
  public static Complex Pow(Complex value, double power)