Swift Tutorial Swift References

Swift - tan() Function

The Swift tan() function returns trigonometric tangent of an angle (angle should be in radians). In the graph below, tan(x) vs x is plotted.

Tan Function


In Foundation framework, it is defined as follows:

public func tan(_ x: CGFloat) -> CGFloat
public func tan(_ x: Float) -> Float
public func tan(_ x: Float80) -> Float80
public func tan(_ __x: Double) -> Double


x Specify the angle in radian.

Return Value

Returns the trigonometric tangent of an angle.


In the example below, tan() function is used to find out the trigonometric tangent of an angle.

import Foundation

var pi = Double.pi

print("tan(pi/6) = \(tan(pi/6))")
print("tan(pi/4) = \(tan(pi/4))")
print("tan(pi/3) = \(tan(pi/3))")

The output of the above code will be:

tan(pi/6) = 0.5773502691896257
tan(pi/4) = 0.9999999999999999
tan(pi/3) = 1.7320508075688767

❮ Swift Math Functions