sin(): Sine of an Angle

sin() returns the vertical coordinate of an angle on the unit circle. It models oscillation, rotation, waves, and periodic motion; sin(0) is 0 and sin(π/2) is 1.

Radians and inverse use

Use radians consistently. Recover a principal angle with asin(), or use atan2() when coordinates determine the quadrant. Pair sin with cos() for circular motion.

Real sine values lie between −1 and 1. Normalize measured ratios before inverse trigonometry, and use abs() when checking amplitude magnitude.