fir error : __init__() takes exactly 2 positional arguments

[priyankaexp]

I am getting an error while trying to fit the model

m = Prophet() m.fit(df)

• Error is

m.fit(df)
File "/Users/priyagupta/anaconda/envs/outlier-detector/lib/python3.5/site-packages/fbprophet/forecaster.py", line 1003, in fit
dat, init=stan_init, iter=1e4, **kwargs)
File "/Users/priyagupta/anaconda/envs/outlier-detector/lib/python3.5/site-packages/pystan/model.py", line 468, in optimizing
fit = self.fit_class(data)
File "stanfit4anon_model_861b75c6337e237650a61ae58c4385ef_6584856068083371156.pyx", line 463, in stanfit4anon_model_861b75c6337e237650a61ae58c4385ef_6584856068083371156.StanFit4Model.init
TypeError: init() takes exactly 2 positional arguments (1 given)

• dataframe contains

df.head()

ds y
0 2018-01-02 8.493219
1 2018-01-03 8.447772
2 2018-01-04 8.453951
3 2018-01-05 8.504886
4 2018-01-06 8.500543

• Python version = 3.5.4 (I specifically need 3.5.* python version)
  anaconda version = 4.2.0
  pystan version = 2.14.0.0
  fbprophet version = 0.3.post2

• I have installed pystan and fbprophet using conda as mention at #pip install fbprophet fails on osx 13.6 #715
  conda install -c conda-forge fbprophet

• I have also tried with sample csv provided at [https://facebook.github.io/prophet/docs/quick_start.html#python-api]
  and this also provides the same error.

Does anyone know, how can I resolve this error?
To me, this looks like a version mismatch between pystan and fbprophet. Do I need to have specific version of fbprophet?

[priyankaexp]

I have also tried the steps mentioned here #324

[priyankaexp]

The issue is solved by installing fbprophet using pip. This installed fbprophet-0.5

[bletham]

hm I'm a bit unsure what happened here. The error was coming from pystan. I wonder if maybe somehow it was trying to use a pystan model that had been pickled under a different version of pystan?. Well, glad to hear that an upgrade fixed it.