how to rotate view in swift 3.0

rorateview.swift

// rotate imageview via 90 degree
myview.transform = CGAffineTransform(rotationAngle: CGFloat.pi / 2) 
// rotate imageview via 180 degree
myview.transform = CGAffineTransform(rotationAngle: CGFloat.pi)
// rotate imageview via 270 degree
myview.transform = CGAffineTransform(rotationAngle: -CGFloat.pi / 2)

// totate iamge
 func imageRotatedByDegrees(oldImage: UIImage,degrees: CGFloat) -> UIImage {
        let size = oldImage.size
        
        UIGraphicsBeginImageContext(size)
        
        let bitmap: CGContext = UIGraphicsGetCurrentContext()!
        //Move the origin to the middle of the image so we will rotate and scale around the center.
        bitmap.translateBy(x: size.width / 2, y: size.height / 2)
        //Rotate the image context
        bitmap.rotate(by: (degrees * CGFloat(M_PI / 180)))
        //Now, draw the rotated/scaled image into the context
        bitmap.scaleBy(x: 1.0, y: -1.0)
        
        let origin = CGPoint(x: -size.width / 2, y: -size.width / 2)
        
        bitmap.draw(oldImage.cgImage!, in: CGRect(origin: origin, size: size))
        
        let newImage: UIImage = UIGraphicsGetImageFromCurrentImageContext()!
        UIGraphicsEndImageContext()
        return newImage
    }