final State state = new State(a, minv, b, x, goodb, shift);
final IterativeLinearSolverEvent event = new SymmLQEvent(this, state);
if (state.beta1 == 0.) {
/* If b = 0 exactly, stop with x = 0. */
manager.fireTerminationEvent(event);
return x;
}
/* Cause termination if beta is essentially zero. */
final boolean earlyStop;
earlyStop = (state.beta < MACH_PREC) || (state.hasConverged);