Math demo (made for mistakes)

README.md

A demo of basic visualization math, written for mistakes

math_demo.js

// Turning an angle into a point on a unit
// circle and then back again

// convert from degrees to radians
D2R = Math.PI / 180;
// convert from radians to degrees
R2D = 180 / Math.PI;

// our angle
angle = 30;
// this angle in radians
radians = angle * D2R;
// point on a unit circle
point = {
  x: Math.cos(radians),
  y: Math.sin(radians)
};

// back to the angle in radians
back = Math.atan2(point.y, point.x);
// back to the angle in degrees
back_angle = back * R2D;