Complex.FromPolarCoordinates(Double, Double) Method

Definition

Creates a complex number from a point's polar coordinates.

C#
public static System.Numerics.Complex FromPolarCoordinates(double magnitude, double phase);

Parameters

magnitude
Double

The magnitude, which is the distance from the origin (the intersection of the x-axis and the y-axis) to the number.

phase
Double

The phase, which is the angle from the line to the horizontal axis, measured in radians.

Returns

A complex number.

Examples

The following example uses the FromPolarCoordinates method to instantiate a complex number based on its polar coordinates and then displays the value of its Magnitude and Phase properties.

C#
using System;
using System.Numerics;

public class Example
{
   public static void Main()
   {
      Complex c1 = Complex.FromPolarCoordinates(10, 45 * Math.PI / 180);
      Console.WriteLine("{0}:", c1);
      Console.WriteLine("   Magnitude: {0}", Complex.Abs(c1));
      Console.WriteLine("   Phase:     {0} radians", c1.Phase);
      Console.WriteLine("   Phase      {0} degrees", c1.Phase * 180/Math.PI);
      Console.WriteLine("   Atan(b/a): {0}", Math.Atan(c1.Imaginary/c1.Real));
   }
}
// The example displays the following output:
//       (7.07106781186548, 7.07106781186547):
//          Magnitude: 10
//          Phase:     0.785398163397448 radians
//          Phase      45 degrees
//          Atan(b/a): 0.785398163397448

Remarks

The FromPolarCoordinates method instantiates a complex number based on its polar coordinates.

Because there are multiple representations of a point on a complex plane, the return value of the FromPolarCoordinates method is normalized. The magnitude is normalized to a positive number, and the phase is normalized to a value in the range of -PI to PI. As a result, the values of the Phase and Magnitude properties of the resulting complex number might not equal the original values of the magnitude and phase parameters.

To convert a value from degrees to radians for the phase parameter, multiply it by π180.

Applies to

Product Versions
.NET Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10
.NET Framework 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 1.1, 1.2, 1.3, 1.4, 1.6, 2.0, 2.1
UWP 10.0

See also