Swift Tutorial Swift References

Swift - sin() Function

The Swift sin() function returns trigonometric sine of an angle (angle should be in radians). The return value will be in the range -1 through 1.

In the graph below, sin(x) vs x is plotted.

Sin Function


In Foundation framework, it is defined as follows:

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


x Specify the angle in radian.

Return Value

Returns the trigonometric sine of an angle.


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

import Foundation

var pi = Double.pi

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

The output of the above code will be:

sin(pi/6) = 0.49999999999999994
sin(pi/4) = 0.7071067811865475
sin(pi/3) = 0.8660254037844386

❮ Swift Math Functions