class_docstr: Original NeRF network.
class_docstr_tok: ["Original","NeRF","network","."]
docstr: Initialize the checkpoints.
docstr_tok: ["Initialize","the","checkpoints","."]
code: def init_checkpoint(self, checkpoint_dir, checkpoint=None):
      """Initialize the checkpoints."""
      self.summary_writer = tf.summary.create_file_writer(
          checkpoint_dir
      )
      self.checkpoint = tf.train.Checkpoint(
          coarse_nerf=self.coarse_model,
          fine_nerf=self.fine_model,
          optimizer_network=self.optimizer_network,
          epoch=self.latest_epoch,
          global_step=self.global_step,
      )
      self.manager = tf.train.CheckpointManager(
          checkpoint=self.checkpoint,
          directory=checkpoint_dir,
          max_to_keep=5,
      )
      self.load_checkpoint(checkpoint=checkpoint)
  
file_path: graphics/tensorflow_graphics/projects/radiance_fields/nerf/model.py
imports: from absl import logging
  import numpy
  import tensorflow
  import tensorflow_graphics.geometry.representation.ray
  import tensorflow_graphics.math.feature_representation
  import tensorflow_graphics.projects.radiance_fields.nerf.layers
  import tensorflow_graphics.projects.radiance_fields.utils
  import tensorflow_graphics.rendering.volumetric.ray_radiance
label_desc: Use image node_id 4 for calling the NeRF obj's underlying member method code with example usage: obj.init_checkpoint(checkpoint_dir, checkpoint) without return types