Math.Atan2-Methode

Gibt einen Winkel zurück, dessen Tangens der Quotient zweier angegebener Zahlen ist.

Namespace: System
Assembly: mscorlib (in mscorlib.dll)

Syntax

'Declaration
Public Shared Function Atan2 ( _
    y As Double, _
    x As Double _
) As Double
'Usage
Dim y As Double
Dim x As Double
Dim returnValue As Double

returnValue = Math.Atan2(y, x)

public static double Atan2 (
    double y,
    double x
)

public:
static double Atan2 (
    double y, 
    double x
)

public static double Atan2 (
    double y, 
    double x
)

public static function Atan2 (
    y : double, 
    x : double
) : double

Parameter

• y
  Die y-Koordinate eines Punkts.

• x
  Die x-Koordinate eines Punkts.

Rückgabewert

Ein Winkel θ im Bogenmaß im Bereich -π≤θ≤π mit tan(θ) = y / x, wobei (x, y) ein Punkt in der kartesischen Ebene ist. Beachten Sie dabei:

• Wenn (x,y) im 1. Quadranten liegt, gilt 0 < θ < π/2.

• Wenn (x, y) im 2. Quadranten liegt, gilt π/2 < θ≤π.

• Wenn (x, y) im 3. Quadranten liegt, gilt -π < θ < -π/2.

• Wenn (x, y) im 4. Quadranten liegt, gilt -π/2 < θ < 0.

Hinweise

Der Rückgabewert ist der Winkel in der kartesischen Ebene zwischen der x-Achse und einem vom Ursprung (0,0) zum Punkt (x,y) zeigenden Vektor.

Beispiel

' This example demonstrates Math.Atan()
'                           Math.Atan2()
'                           Math.Tan()
Imports System

Class Sample
   Public Shared Sub Main()
      Dim x As Double = 1.0
      Dim y As Double = 2.0
      Dim angle As Double
      Dim radians As Double
      Dim result As Double
      
      ' Calculate the tangent of 30 degrees.
      angle = 30
      radians = angle *(Math.PI / 180)
      result = Math.Tan(radians)
      Console.WriteLine("The tangent of 30 degrees is {0}.", result)
      
      ' Calculate the arctangent of the previous tangent.
      radians = Math.Atan(result)
      angle = radians *(180 / Math.PI)
      Console.WriteLine("The previous tangent is equivalent to {0} degrees.", angle)
      
      ' Calculate the arctangent of an angle.
      Dim line1 As [String] = "{0}The arctangent of the angle formed by the x-axis and "
      Dim line2 As [String] = "a vector to point ({0},{1}) is {2}, "
      Dim line3 As [String] = "which is equivalent to {0} degrees."
      
      radians = Math.Atan2(y, x)
      angle = radians *(180 / Math.PI)
      
      Console.WriteLine(line1, Environment.NewLine)
      Console.WriteLine(line2, x, y, radians)
      Console.WriteLine(line3, angle)
   End Sub 'Main
End Class 'Sample
'
'This example produces the following results:
'
'The tangent of 30 degrees is 0.577350269189626.
'The previous tangent is equivalent to 30 degrees.
'
'The arctangent of the angle formed by the x-axis and
'a vector to point (1,2) is 1.10714871779409,
'which is equivalent to 63.434948822922 degrees.
'

// This example demonstrates Math.Atan()
//                           Math.Atan2()
//                           Math.Tan()
using System;

class Sample 
{
    public static void Main() 
    {
    double x = 1.0;
    double y = 2.0;
    double angle;
    double radians;
    double result;

// Calculate the tangent of 30 degrees.
    angle = 30;
    radians = angle * (Math.PI/180);
    result = Math.Tan(radians);
    Console.WriteLine("The tangent of 30 degrees is {0}.", result);

// Calculate the arctangent of the previous tangent.
    radians = Math.Atan(result);
    angle = radians * (180/Math.PI);
    Console.WriteLine("The previous tangent is equivalent to {0} degrees.", angle);

// Calculate the arctangent of an angle.
    String line1 = "{0}The arctangent of the angle formed by the x-axis and ";
    String line2 = "a vector to point ({0},{1}) is {2}, ";
    String line3 = "which is equivalent to {0} degrees.";

    radians = Math.Atan2(y, x);
    angle = radians * (180/Math.PI);

    Console.WriteLine(line1, Environment.NewLine);
    Console.WriteLine(line2, x, y, radians);
    Console.WriteLine(line3, angle);
    }
}
/*
This example produces the following results:

The tangent of 30 degrees is 0.577350269189626.
The previous tangent is equivalent to 30 degrees.

The arctangent of the angle formed by the x-axis and
a vector to point (1,2) is 1.10714871779409,
which is equivalent to 63.434948822922 degrees.
*/

// This example demonstrates Math.Atan()
//                           Math.Atan2()
//                           Math.Tan()
using namespace System;
int main()
{
   double x = 1.0;
   double y = 2.0;
   double angle;
   double radians;
   double result;
   
   // Calculate the tangent of 30 degrees.
   angle = 30;
   radians = angle * (Math::PI / 180);
   result = Math::Tan( radians );
   Console::WriteLine( "The tangent of 30 degrees is {0}.", result );
   
   // Calculate the arctangent of the previous tangent.
   radians = Math::Atan( result );
   angle = radians * (180 / Math::PI);
   Console::WriteLine( "The previous tangent is equivalent to {0} degrees.", angle );
   
   // Calculate the arctangent of an angle.
   String^ line1 = "{0}The arctangent of the angle formed by the x-axis and ";
   String^ line2 = "a vector to point ({0},{1}) is {2}, ";
   String^ line3 = "which is equivalent to {0} degrees.";
   radians = Math::Atan2( y, x );
   angle = radians * (180 / Math::PI);
   Console::WriteLine( line1, Environment::NewLine );
   Console::WriteLine( line2, x, y, radians );
   Console::WriteLine( line3, angle );
}

/*
This example produces the following results:

The tangent of 30 degrees is 0.577350269189626.
The previous tangent is equivalent to 30 degrees.

The arctangent of the angle formed by the x-axis and
a vector to point (1,2) is 1.10714871779409,
which is equivalent to 63.434948822922 degrees.
*/

// This example demonstrates Math.Atan()
//                           Math.Atan2()
//                           Math.Tan()

import System.*;

class Sample
{
    public static void main(String[] args)
    {
        double x = 1.0;
        double y = 2.0;
        double angle;
        double radians;
        double result;

        // Calculate the tangent of 30 degrees.
        angle = 30;
        radians = angle * (Math.PI / 180);
        result = System.Math.Tan(radians);
        Console.WriteLine("The tangent of 30 degrees is {0}.", 
            System.Convert.ToString(result));

        // Calculate the arctangent of the previous tangent.
        radians = System.Math.Atan(result);
        angle = radians * (180 / Math.PI);
        Console.WriteLine("The previous tangent is equivalent to {0} degrees.",
            System.Convert.ToString(angle));

        // Calculate the arctangent of an angle.
        String line1 = "{0}The arctangent of the angle formed by"
            + " the x-axis and ";
        String line2 = "a vector to point ({0},{1}) is {2}, ";
        String line3 = "which is equivalent to {0} degrees.";

        radians = System.Math.Atan2(y, x);
        angle = radians * (180 / Math.PI);

        Console.WriteLine(line1, Environment.get_NewLine());
        Console.WriteLine(line2, System.Convert.ToString(x), 
            System.Convert.ToString(y), System.Convert.ToString(radians));
        Console.WriteLine(line3, System.Convert.ToString(angle));
    } //main
} //Sample

/*
This example produces the following results:

The tangent of 30 degrees is 0.577350269189626.
The previous tangent is equivalent to 30 degrees.

The arctangent of the angle formed by the x-axis and
a vector to point (1,2) is 1.10714871779409,
which is equivalent to 63.434948822922 degrees.
*/

Plattformen

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile für Pocket PC, Windows Mobile für Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

.NET Framework unterstützt nicht alle Versionen sämtlicher Plattformen. Eine Liste der unterstützten Versionen finden Sie unter Systemanforderungen.

Versionsinformationen

.NET Framework

Unterstützt in: 2.0, 1.1, 1.0

.NET Compact Framework

Unterstützt in: 2.0, 1.0

Siehe auch

Referenz

Math-Klasse
Math-Member
System-Namespace