download_and_convert_mnist.py 文件源码

def _extract_labels(filename, num_labels):
  """Extract the labels into a vector of int64 label IDs.

  Args:
    filename: The path to an MNIST labels file.
    num_labels: The number of labels in the file.

  Returns:
    A numpy array of shape [number_of_labels]
  """
  print('Extracting labels from: ', filename)
  with gzip.open(filename) as bytestream:
    bytestream.read(8)
    buf = bytestream.read(1 * num_labels)
    labels = np.frombuffer(buf, dtype=np.uint8).astype(np.int64)
  return labels