code: private int[] readDimension(ByteBuffer buf ) throws IOException
      {
          
          ISMatTag tag = new ISMatTag(buf);
          int[] dims = tag.readToIntArray();
          return dims;
          
      }
docs: Reads Matrix dimensions.
  
  Modifies <code>buf</code> position.
  
  @param buf <code>ByteBuffer</code>
  @return dimensions int array
  @throws IOException if reading from buffer fails