Polynom NewtonBinomial::expandPolynom(
double y, unsigned int degree)
{
Combination combination;
Polynom polynom;
polynom.getCoefs().resize(degree + 1);
for (size_t k=0;k<=degree;k++) {
polynom.getCoefs()[k] =
combination.binomialCoefficient(k, degree)
* pow(y, degree-k);
}
return polynom;
}
Polynom CubicSpline::polynomFit(double t,
double pos1, double vel1,
double pos2, double vel2) const
{
if (t <= 0.00001) {
throw std::logic_error(
"CubicSpline invalid spline interval");
}
double t2 = t*t;
double t3 = t2*t;
Polynom p;
p.getCoefs().resize(4);
p.getCoefs()[0] = pos1;
p.getCoefs()[1] = vel1;
p.getCoefs()[3] = (vel2 - vel1 - 2.0*(pos2-pos1-vel1*t)/t)/t2;
p.getCoefs()[2] = (pos2 - pos1 - vel1*t - p.getCoefs()[3]*t3)/t2;
return p;
}