code: def _parse_libsvm_line(line):
          
          items = line.split(None)
          label = float(items[0])
          nnz = len(items) - 1
          indices = np.zeros(nnz, dtype=np.int32)
          values = np.zeros(nnz)
          for i in xrange(nnz):
              index, value = items[1 + i].split(":")
              indices[i] = int(index) - 1
              values[i] = float(value)
          return label, indices, values
docs: Parses a line in LIBSVM format into (label, indices, values).