Factor product failing

[Gabriel Azevedo Ferreira]

Subject of the issue

Describe your issue here.

import pandas as pd
from pgmpy.factors import factor_product
from pgmpy.factors.discrete import TabularCPD
import numpy as np

aux=np.random.rand(3,3 *3 *3)
cpd1 = TabularCPD(
    variable='z',
    variable_card=3,
    values=np.divide(aux,aux.sum(axis=0)),
    evidence=['p_0', 'p_1','p_2'],
    evidence_card=[3, 3, 3],
)

aux=np.random.rand(3,3)
cpd2 = TabularCPD(
    variable='c_0',
    variable_card=3,
    values=np.divide(aux,aux.sum(axis=0)),
    evidence=['z'],
    evidence_card=[3],
)

aux=np.random.rand(3,3)
cpd3 = TabularCPD(
    variable='c_1',
    variable_card=3,
    values=np.divide(aux,aux.sum(axis=0)),
    evidence=['z'],
    evidence_card=[3],
)

factor_product(cpd1, cpd2, cpd3)

error message:

/lib/python3.8/site-packages/pgmpy/factors/discrete/DiscreteFactor.py in __init__(self, variables, cardinality, values, state_names)
     97 
     98         if len(set(variables)) != len(variables):
---> 99             raise ValueError("Variable names cannot be same")
    100 
    101         if not isinstance(state_names, dict):

ValueError: Variable names cannot be same

Versions:
pgmpy==0.1.20
python 3.8
Linux and Mac

Your environment

• pgmpy version
• Python version
• Operating System

Steps to reproduce

Tell us how to reproduce this issue. Please provide a minimal reproducible code of
the issue you are facing if possible.

Expected behaviour

Tell us what should happen

Actual behaviour

Tell us what happens instead

[Ankur Ankan]

@GabrielAzevedoFerreiraQB The factor_product method expects the arguments to be DiscreteFactor objects, so you will need to explicitly convert the CPDs to factor objects. Something like this works:

In [20]: factor_product(cpd1.to_factor(), cpd2.to_factor(), cpd3.to_factor())
Out[20]: <DiscreteFactor representing phi(c_1:3, c_0:3, z:3, p_0:3, p_1:3, p_2:3) at 0x7f09ed840130>