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| export const calculateRadius = (fs, s) => {
| const alpha = approximateAlpha(fs, s);
| const radius = s/(2*Math.sin(alpha/2));
| return [radius, alpha];
| }
|
| const approximateAlpha = (fs, s) => {
| console.log({fs, s});
| const Y = 8*fs/(s**2);
| let left = 0;
| let right = Math.PI;
| // f(alpha) = (alpha - sin(alpha)) / (sin^2(alpha/2))
| const EPSILON = 0.001;
| let alpha = 0 ;
| let y = 0;
| let diff = 2*EPSILON;
| do{
| alpha = (left + right)/2;
| y = (alpha - Math.sin(alpha)) / ( Math.sin(alpha/2)**2 ) ;
| diff = y - Y;
| if(diff < 0) {
| left = alpha;
| }else{
| right = alpha;
| }
| } while( Math.abs(diff) >= EPSILON);
| return alpha;
| }
|
|
