String fileDelimiter = ",";
RecordReader featuresReader = new CSVRecordReader(numLinesToSkip,fileDelimiter);
String featuresCsvPath = "/path/to/my/myInput.csv";
featuresReader.initialize(new FileSplit(new File(featuresCsvPath)));
RecordReader labelsReader = new CSVRecordReader(numLinesToSkip,fileDelimiter);
String labelsCsvPath = "/path/to/my/myOutput.csv";
labelsReader.initialize(new FileSplit(new File(labelsCsvPath)));
MultiDataSetIterator iterator = new RecordReaderMultiDataSetIterator.Builder(batchSize)
.addReader("csvInput", featuresReader)
.addReader("csvLabels", labelsReader)
.addInput("csvInput") //Input: all columns from input reader
.addOutput("csvLabels", 0, 3) //Output 1: columns 0 to 3 inclusive
.addOutputOneHot("csvLabels", 4, numClasses) //Output 2: column 4 -> convert to one-hot for classification