Class SumReducer

src/com/winvector/logistic/mr/MapRedFn.java:265–276

	}
	
	public static final class SumReducer extends Reducer<Text,DoubleWritable,Text,DoubleWritable> { // TODO: check if there is a standard summer we could use here
		@Override
		public void reduce(final Text key, final Iterable<DoubleWritable> values, final Context context) throws IOException, InterruptedException {
			double total = 0.0;
			for(final DoubleWritable vi: values) {
				total += vi.get();
			}
			if(total!=0.0) {
				context.write(new Text(key.toString()),new DoubleWritable(total));
			}
		}
	}
	
	@Override
	public VEval eval(final double[] x, final boolean wantGrad, final boolean wantHessian) {