# Double - Atan2

Returns the angle whose tangent is the quotient of two specified numbers.

```public static void Main()
{
double x = 1.0;
double y = 2.0;
double angle;

// Calculate the tangent of 30 degrees.
angle = 30;
radians = angle * (Math.PI / 180);

// C# Extension Method: Double - Atan2
angle = radians * (180 / Math.PI);

Console.WriteLine("The arctangent of the angle formed by the x-axis and ");
Console.WriteLine("a vector to point ({0},{1}) is {2}, ", x, y, radians);
Console.WriteLine("which is equivalent to {0} degrees.", angle);

}
```

View Source
```using System;

public static partial class Extensions
{
/// <summary>
///     Returns the angle whose tangent is the quotient of two specified numbers.
/// </summary>
/// <param name="y">The y coordinate of a point.</param>
/// <param name="x">The x coordinate of a point.</param>
/// <returns>
///     An angle, ?, measured in radians, such that -?????, and tan(?) =  / , where (, ) is a point in the Cartesian
///     plane. Observe the following: For (, ) in quadrant 1, 0 &lt; ? &lt; ?/2.For (, ) in quadrant 2, ?/2 &lt;
///     ???.For (, ) in quadrant 3, -? &lt; ? &lt; -?/2.For (, ) in quadrant 4, -?/2 &lt; ? &lt; 0.For points on the
///     boundaries of the quadrants, the return value is the following:If y is 0 and x is not negative, ? = 0.If y is
///     0 and x is negative, ? = ?.If y is positive and x is 0, ? = ?/2.If y is negative and x is 0, ? = -?/2.If  or
///     is , or if  and  are either  or , the method returns .
/// </returns>
public static Double Atan2(this Double y, Double x)
{
return Math.Atan2(y, x);
}
}
```