Method accuracy

src/com/winvector/opt/impl/HelperFns.java:70–79

(final DModel<T> fn, final Iterable<T> as, final double[] x)

	}
	
	public static <T extends ExampleRow> double accuracy(final DModel<T> fn, final Iterable<T> as, final double[] x) {
		final AccuracyCounter<T> counter = new AccuracyCounter<T>(fn,x);
		final Log log = LogFactory.getLog(fn.getClass());
		final String logString = fn.getClass().getName() + " accuracy scan";
		final ThreadedReducer<T,AccuracyCounter<T>,AccuracyCounter<T>> reducer = new ThreadedReducer<T,AccuracyCounter<T>,AccuracyCounter<T>>(5,logString);
		reducer.reduce(as,counter);
		final double accuracy = counter.nGood/(double)counter.n; 
		log.info("accuarcy: " + counter.nGood + "/" + counter.n + " = " + accuracy);
		return accuracy;
	}
	
	public static double dot(final Datum row, final double[] o, final int startIndex) {
		double r = 0.0;