fastBellFunc function

double fastBellFunc(
  1. double x
)

Implementation

double fastBellFunc(double x) {
  var x2 = x * x;
  if (x2 <= 0.25) return 1 - 2 * x2;
  return (1 - x2) / (8 * x2) + 1 / 8.0;
}