tensorflow_backend.py 文件源码

def concatenate(tensors, axis=-1):
    """Concatenates a list of tensors alongside the specified axis.

    # Returns
        A tensor.
    """
    if axis < 0:
        dims = ndim(tensors[0])
        if dims:
            axis = axis % dims
        else:
            axis = 0

    if py_all([is_sparse(x) for x in tensors]):
        return tf.sparse_concat(axis, tensors)
    else:
        if tf_major_version >= 1:
            return tf.concat([to_dense(x) for x in tensors], axis)
        else:
            try:
                return tf.concat_v2([to_dense(x) for x in tensors], axis)
            except AttributeError:
                return tf.concat(axis, [to_dense(x) for x in tensors])