Math::Atan Method
Returns the angle whose tangent is the specified number.
Namespace: System
Assembly: mscorlib (in mscorlib.dll)
Parameters
- d
- Type: System::Double
A number representing a tangent.
Return Value
Type: System::DoubleAn angle, θ, measured in radians, such that -π/2 ≤ θ ≤ π/2.
-or-
NaN if d equals NaN, -π/2 rounded to double precision (-1.5707963267949) if d equals NegativeInfinity, or π/2 rounded to double precision (1.5707963267949) if d equals PositiveInfinity.
A positive return value represents a counterclockwise angle from the x-axis; a negative return value represents a clockwise angle.
Multiply the return value by 180/Math::PI to convert from radians to degrees.
The following example demonstrates how to calculate the arctangent of a value and display it to the console.
// 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. */
Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
