ValueError: x and y must have same first dimension, but have shapes (0,) and (1,)

[1632325673]

Evaluation:
0it [00:00, ?it/s]
[div2k x2] PSNR: nan (Best: nan @epoch 1)
Forward: 1.97s

Saving...
Traceback (most recent call last):
File "main.py", line 33, in
main()
File "main.py", line 28, in main
t.test()
File "/data2/qinfl/EDSR/src/trainer.py", line 123, in test
self.ckp.save(self, epoch, is_best=(best[1][0, 0] + 1 == epoch))
File "/data2/qinfl/EDSR/src/utility.py", line 97, in save
self.plot_psnr(epoch)
File "/data2/qinfl/EDSR/src/utility.py", line 124, in plot_psnr
label='Scale {}'.format(scale)
File "/data2/qinfl/YES/envs/EDSR1/lib/python3.6/site-packages/matplotlib/pyplot.py", line 2842, in plot
**({"data": data} if data is not None else {}), **kwargs)
File "/data2/qinfl/YES/envs/EDSR1/lib/python3.6/site-packages/matplotlib/axes/_axes.py", line 1743, in plot
lines = [*self._get_lines(*args, data=data, **kwargs)]
File "/data2/qinfl/YES/envs/EDSR1/lib/python3.6/site-packages/matplotlib/axes/_base.py", line 273, in call
yield from self._plot_args(this, kwargs)
File "/data2/qinfl/YES/envs/EDSR1/lib/python3.6/site-packages/matplotlib/axes/_base.py", line 399, in _plot_args
raise ValueError(f"x and y must have same first dimension, but "
ValueError: x and y must have same first dimension, but have shapes (0,) and (1,)