System Namespace   Math Class

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

[ VB ]
Public Shared Function Atan2 ( _
   ByVal y As Double, _
   ByVal x As Double _
) As Double

[ C# ]
public static double Atan2 (
   double y,
   double x
);

[ C++ ]
public: static double Atan2 (
   double y,
   double x
);

[ JScript ]
public static function Atan2 (
   y : double,
   x : double
) : double;

y

The y coordinate of a point.

x

The x coordinate of a point.

An angle, q, measured in radians, such that -π < q ≤ π, and tan ( q ) = y/ x, where ( x, y ) is a point in the Cartesian plane. Observe the following:

• For ( x, y ) in quadrant 1, 0 < q < π/2.
• For ( x, y ) in quadrant 2, π/2 < q ≤ π.
• For ( x, y ) in quadrant 3, -π < q < -π/2.
• For ( x, y ) in quadrant 4, -π/2 < q < 0.

The return value is the angle in the Cartesian plane formed by the x-axis, and a vector starting from the origin, ( 0,0 ) , and terminating at the point, ( x,y ) .

Math Members

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