}
final double rhoNext = r.dotProduct(z);
if (check && (rhoNext <= 0.)) {
final NonPositiveDefiniteOperatorException e;
e = new NonPositiveDefiniteOperatorException();
final ExceptionContext context = e.getContext();
context.setValue(OPERATOR, m);
context.setValue(VECTOR, r);
throw e;
}
if (manager.getIterations() == 2) {
p.setSubVector(0, z);
} else {
p.combineToSelf(rhoNext / rhoPrev, 1., z);
}
q = a.operate(p);
final double pq = p.dotProduct(q);
if (check && (pq <= 0.)) {
final NonPositiveDefiniteOperatorException e;
e = new NonPositiveDefiniteOperatorException();
final ExceptionContext context = e.getContext();
context.setValue(OPERATOR, a);
context.setValue(VECTOR, p);
throw e;
}
final double alpha = rhoNext / pq;
x.combineToSelf(1., alpha, p);
r.combineToSelf(1., -alpha, q);