Method eval

src/com/winvector/logistic/mr/MapRedFn.java:278–322

(final double[] x, final boolean wantGrad, final boolean wantHessian)

	}
	
	@Override
	public VEval eval(final double[] x, final boolean wantGrad, final boolean wantHessian) {
		try {
			final String pathOutName = tmpPrefix + "_MPRedFnOut";
			final Path pathOut = new Path(pathOutName);
			final JobStateDescr conf = new JobStateDescr();
			conf.underlying = underlying;
			conf.defs = defs;
			conf.x = x;
			conf.useIntercept = useIntercept;
			conf.wantGrad = wantGrad;
			conf.wantHessian = wantHessian;
			mrConfig.set(MRFIELDNAME,conf.toString()); // prepare config for distribution
			// run the job
			final Job job = WritableUtils.newJob(mrConfig);
			job.setJarByClass(MapRedFn.class);
			job.setJobName("MapRedFnStep");
			FileInputFormat.setMaxInputSplitSize(job,4*1024*1024L);
			FileInputFormat.setMinInputSplitSize(job,4*1024L);
			FileInputFormat.addInputPath(job, pathIn);
			FileOutputFormat.setOutputPath(job, pathOut);
			job.setMapperClass(SumMapper.class);
			job.setCombinerClass(SumReducer.class);
			job.setReducerClass(SumReducer.class);
			job.setOutputKeyClass(Text.class);
			job.setOutputValueClass(DoubleWritable.class);
			job.setInputFormatClass(TextInputFormat.class);
			job.setOutputFormatClass(TextOutputFormat.class);
			job.setNumReduceTasks(1);
			final VEval r = new VEval(x,wantGrad,wantHessian);
			if(job.waitForCompletion(false)) {
				// collect results
				final FSDataInputStream fdi = pathOut.getFileSystem(mrConfig).open(new Path(pathOut,"part-r-00000"));
				final BufferedReader d = new BufferedReader(new InputStreamReader(fdi));
				SumMapper.addVEvalFromBufferedReader(r,d);
		        d.close();
			}
			// clean up
			pathOut.getFileSystem(mrConfig).delete(pathOut,true);
			return r;
		} catch (Exception ex) {
			log.error("caught: " + ex);
			throw new RuntimeException(ex);
		}
	}
	
}