BaseEstimator.state_counts() erroneously reports zero for nodes with a single parent

[mellesies]

When computing state counts for nodes with a single parent, the function BaseEstimator.state_counts() erroneously reports zero:

import pandas as pd

from pgmpy.models import BayesianModel
from pgmpy.estimators import BaseEstimator, ParameterEstimator

# Generate the data
data = pd.DataFrame(data={'fruit': ["banana", "apple", "banana", "apple", "banana","apple", "banana", 
                                    "apple", "apple", "apple", "banana", "banana", "apple", "banana",], 
                          'tasty': ["yes", "no", "yes", "yes", "yes", "yes", "yes", 
                                    "yes", "yes", "yes", "yes", "no", "no", "no"], 
                          'size': ["large", "large", "large", "small", "large", "large", "large",
                                    "small", "large", "large", "large", "large", "small", "small"]})

be = BaseEstimator(data)
print(be.state_counts('tasty', parents=['fruit']))  # conditional on fruit

Yields:

 fruit apple banana
tasty             
no      0.0    0.0
yes     0.0    0.0

Which should be:

fruit  apple  banana
tasty               
no         2       2
yes        5       5

[mellesies]

Sorry .. mistakenly posted this issue to the wrong project.