Swift - atan2() Function
The Swift atan2() function returns the angle theta from the conversion of rectangular coordinates (x, y) to polar coordinates (r, theta). The returned value will be in the range -𝜋 through 𝜋.
Syntax
In Foundation framework, it is defined as follows:
public func atan2(_ __y: Double, _ __x: Double) -> Double
Parameters
y |
Specify the ordinate coordinate. |
x |
Specify the abscissa coordinate. |
Return Value
Returns theta of the point (r, theta) in polar coordinates that corresponds to the point (x, y) in Cartesian coordinates.
Example:
In the example below, atan2() function is used to calculate the theta of a point.
import Foundation print("atan2(1.0, 1.0) = \(atan2(1.0, 1.0))") print("atan2(1.0, 2.0) = \(atan2(1.0, 2.0))") print("atan2(2.0, 1.0) = \(atan2(2.0, 1.0))") print("atan2(-1.0, 2.0) = \(atan2(-1.0, 2.0))") print("atan2(-1.0, -2.0) = \(atan2(-1.0, -2.0))")
The output of the above code will be:
atan2(1.0, 1.0) = 0.7853981633974483 atan2(1.0, 2.0) = 0.4636476090008061 atan2(2.0, 1.0) = 1.1071487177940904 atan2(-1.0, 2.0) = -0.4636476090008061 atan2(-1.0, -2.0) = -2.677945044588987
❮ Swift Math Functions