Radian
Radians is defined by the ratio of the length of the arc of a circle (a segment of the circle’s circumference) to the radius of that circle.
- One radian is the angle at which that ratio equals 1
- A full circle (360 degrees) is equivalent to 2π radians
- 180 degrees is equivalent to π radians
- 90 degrees is equivalent to π/2 radians.
The formula to convert from degrees to radians is as follows:
radians = 2π × degrees / 360