/**
* Find the smallest real root of p within lowerBound and upperBound (bounds may or may not be
* included). If no real root exists in this interval, Double.NaN ist returned.
*
* @param p
* @param lowerBound
* @param upperBound
* @return
*/
public double findFirstRootIn(UnivariatePolynomial p, double lowerBound, double upperBound) {
if (makeSquarefree) {
// make p squarefree
UnivariatePolynomial gcd = UnivariatePolynomial.gcd(p, p.derive());
if (gcd.degree() > 0)
// Polynomial not squarefree!
p = p.div(gcd);
}
return EVAL(p, lowerBound, upperBound, p.evaluateAt(lowerBound), p.evaluateAt(upperBound));
}
private static double bisect(UnivariatePolynomial p, double lowerBound, double upperBound) {
return bisect(p, lowerBound, upperBound, p.evaluateAt(lowerBound), p.evaluateAt(upperBound));
}