code: public static double[][][] readQuantizers(String[] filenames, int[] numCentroids, int centroidLength)
  			throws IOException {
  		int numQuantizers = filenames.length;
  		double[][][] quantizers = new double[numQuantizers][][];
  		for (int i = 0; i < numQuantizers; i++) {
  			quantizers[i] = AbstractFeatureAggregator.readQuantizer(filenames[i], numCentroids[i],
  					centroidLength);
  		}
  		return quantizers;
  
  	}
docs: Reads multiple quantizers (codebooks) from the given files and returns them in a 3-dimensional double
  array.
  
  @param filenames
  names of the files containing the quantizers
  @param numCentroids
  numbers of centroids of each quantizer
  @param centroidLength
  length of each centroid
  @return the quantizers as a 3-dimensional double array
  @throws IOException