fastSin function

dynamic fastSin(
  1. double x
)

Implementation

fastSin(double x) {
  if (x < 0) {
    return 1.27323954 * x + 0.405284735 * x * x;
  } else {
    return 1.27323954 * x - 0.405284735 * x * x;
  }
}