/**
* The constructor creates a Quotient object from a ring factory and a numerator and denominator
* element.
*
* @param r ring factory.
* @param n numerator.
* @param d denominator.
* @param isred true if gcd(n,d) == 1, else false.
*/
@SuppressWarnings("unchecked")
protected Quotient(QuotientRing<C> r, C n, C d, boolean isred) {
if (d == null || d.isZERO()) {
throw new IllegalArgumentException("denominator may not be zero");
}
ring = r;
if (d.signum() < 0) {
n = n.negate();
d = d.negate();
}
if (isred) {
num = n;
den = d;
return;
}
// must reduce to lowest terms
if (n instanceof GcdRingElem && d instanceof GcdRingElem) {
GcdRingElem ng = (GcdRingElem) n;
GcdRingElem dg = (GcdRingElem) d;
C gcd = (C) ng.gcd(dg);
if (debug) {
logger.info("gcd = " + gcd);
}
// RingElem<C> gcd = ring.ring.getONE();
if (gcd.isONE()) {
num = n;
den = d;
} else {
num = n.divide(gcd);
den = d.divide(gcd);
}
// } else { // univariate polynomial?
} else {
logger.warn("gcd = ????");
num = n;
den = d;
}
}
/**
* Quotient negate.
*
* @return -this.
* @see edu.jas.structure.RingElem#negate()
*/
public Quotient<C> negate() {
return new Quotient<C>(ring, num.negate(), den, true);
}
