Pass empty directory to tf.train.get_checkpoint_state()

Hello, I’m completely new to tensorflow. Right now I’m trying
out a
training script on two different datasets using tensorflow
1.13.0, and got stuck when it was trying to pass an empty directory
PRETRAINED_MODEL_PATH to
tf.train.get_checkpoint_state(PRETRAINED_MODEL_PATH),

PRETRAINED_MODEL_PATH = '' saver = tf.train.Saver([v for v in tf.get_collection_ref(tf.GraphKeys.GLOBAL_VARIABLES) if('lr' not in v.name) and ('batch' not in v.name)]) ckptstate = tf.train.get_checkpoint_state(PRETRAINED_MODEL_PATH) 

The two datasets are getting two different responses when
passing an empty directory to tf.train.get_checkpoint_state(). The
first dataset I tried outputs a warning, but the training
continues.

WARNING:tensorflow:FailedPreconditionError: checkpoint; Is a directory WARNING:tensorflow:checkpoint: Checkpoint ignored 

The second dataset I tried outputs an error and script ends.

Traceback (most recent call last): File "cam_est/train_sdf_cam.py", line 827, in <module> train() File "cam_est/train_sdf_cam.py", line 495, in train ckptstate = tf.train.get_checkpoint_state(PRETRAINED_MODEL_PATH) File "/home/jg/anaconda3/envs/tf_trimesh/lib/python3.6/site-packages/tensorflow/python/training/checkpoint_management.py", line 278, in get_checkpoint_state + checkpoint_dir) ValueError: Invalid checkpoint state loaded from 

I have tried everything I can think of but still can’t figure
out the problem. Can someone help please?