ValueError: need at least one array to concatenate

[Amlan1996]

Hi,

I am trying to MCEvidence for the first regarding on of project which required the calculation of bayesian evidence. I ran W0-Wa CDM model in montepython and used the chains obtained from the run to calculate the evidence. However I am encountering the following error:

[amlan@nova MCEvidence]$ python MCEvidence.py /home/amlan/mp/chains/desi_ppb4/
INFO:MCEvidence.py.params_info():1235     getting params info from montepython log.params file
INFO:MCEvidence.py.get_prior_volume():1319     getting prior volume using cosmomc *.ranges or montepython log.param outputs
INFO:MCEvidence.py.get_prior_volume():1320     prior_volume=109.25839039999998
INFO:MCEvidence.py.get_prior_volume():1321     Number of params to use: ndim=8

Using file:  /home/amlan/mp/chains/desi_ppb4/
INFO:MCEvidence.py.setup():142      Loading chain from /home/amlan/mp/chains/desi_ppb4/
INFO:MCEvidence.py.load_from_file():595       loading files: /home/amlan/mp/chains/desi_ppb4/_?.txt
Traceback (most recent call last):
  File "MCEvidence.py", line 1469, in <module>
    thinlen=thinlen)
  File "MCEvidence.py", line 753, in __init__
    self.gd = MCSamples(method,csplit=csplit,debug=self.debug,**gdkwargs)
  File "MCEvidence.py", line 557, in __init__
    self.setup(str_or_dict,**kwargs)
  File "MCEvidence.py", line 143, in setup
    self.data = self.load_from_file(fileroot,**kwargs)            
  File "MCEvidence.py", line 606, in load_from_file
    return self.chains2samples(**kwargs)
  File "MCEvidence.py", line 197, in chains2samples
    self.ichain=np.concatenate([(i+1)*np.ones(len(c)) for i, c in enumerate(self.chains)])
  File "<__array_function__ internals>", line 6, in concatenate
ValueError: need at least one array to concatenate

It would be great if you could help me resolve this issue.

Best regards,
Amlan