toeInv function

double toeInv(
  1. double x
)

Implementation

double toeInv(double x) {
  const double k1 = 0.206;
  const double k2 = 0.03;
  const double k3 = (1 + k1) / (1 + k2);
  return (x * x + k1 * x) / (k3 * (x + k2));
}