How to use CGAffineTransformMakeRotation?

Question

CGAffineTransformMakeRotation expects angle in radians, not in degrees.

#define DEGREES_TO_RADIANS(x) (M_PI * (x) / 180.0)
...

CGAffineTransformMakeRotation(DEGREES_TO_RADIANS(45));

[view setTransform:CGAffineTransformMakeRotation(M_PI / 2)];