Pystan Windows Reinstall

pystanInstall.txt

1 . Open CMD.exe as ADMIN
2. Install Chocolatery :  @"%SystemRoot%\System32\WindowsPowerShell\v1.0\powershell.exe" -NoProfile -InputFormat None -ExecutionPolicy Bypass -Command "iex ((New-Object System.Net.WebClient).DownloadString('https://chocolatey.org/install.ps1'))" && SET "PATH=%PATH%;%ALLUSERSPROFILE%\chocolatey\bin"

https://chocolatey.org/install

3. Update Python : choco install python --pre

https://chocolatey.org/packages/python

4. Install Anaconda : https://www.anaconda.com/download/

5 . Open Anaconda Prompt and install Pystan : 
              - conda install numpy
              - conda install cython

6. Install Pystan in Anaconda Prompt : pip install pystan 
6. bis d'ont forget to install mingw and add it to the path : mingw.org
7. test if pystan was correctly installed (run in anaconda prompt or jupiter)

import pystan
model_code = 'parameters {real y;} model {y ~ normal(0,1);}'
model = pystan.StanModel(model_code=model_code)
y = model.sampling(n_jobs=1).extract()['y']
y.mean()