True_scores has a large number of 'nan' causing errors in calculating 'acc'

[Zjz12138]

True_scores has a large number of 'nan' causing errors in calculating 'acc'.

[Zjz12138]

Suspected to be caused by '02_generation_dataset. py', I added code in 'utilities. py':
print(sample_scores[sample_action_set])
It was found that 'Nan' would be output, which is incorrect.
Suggest rewriting '02_generation_dataset. py'.

[Zjz12138]

"
env = ecole.environment.Branching(observation_function=observation_function,
scip_params=scip_parameters, pseudo_candidates=True)
"

Maybe it's because of this'pseudo_candidates=True'.