failed to import psycho backend

Comments

• sebastiaan

  June 2018

  Hi Roelof,

  The error seems to come from scipy, more specifically the scipy.optimize module. If you import this module on its own, do you get the same error?

  Cheers,
  Sebastiaan

  
  
  Check out SigmundAI.eu for our OpenSesame AI assistant!
  
• Roelof

  June 2018

  Hi Sebastiaan,

  Thank you for the response and suggestion, importing the module on its own (import scipy) gives no errors, but importing the specific module gives:

  from scipy import optimize
  
  ImportErrorTraceback (most recent call last)
  <ipython-input-2-b32e70e68d77> in <module>()
  ----> 1 from scipy import optimize
  
  C:\Program Files (x86)\_PortableOpenSesameS\opensesame_3.1.9-py2.7-win32-1\lib\site-packages\scipy\optimize\__init__.py in <module>()
      231 
      232 from .optimize import *
  --> 233 from ._minimize import *
      234 from ._root import *
      235 from .minpack import *
  
  C:\Program Files (x86)\_PortableOpenSesameS\opensesame_3.1.9-py2.7-win32-1\lib\site-packages\scipy\optimize\_minimize.py in <module>()
       28 
       29 # constrained minimization
  ---> 30 from .lbfgsb import _minimize_lbfgsb
       31 from .tnc import _minimize_tnc
       32 from .cobyla import _minimize_cobyla
  
  C:\Program Files (x86)\_PortableOpenSesameS\opensesame_3.1.9-py2.7-win32-1\lib\site-packages\scipy\optimize\lbfgsb.py in <module>()
       38 import numpy as np
       39 from numpy import array, asarray, float64, int32, zeros
  ---> 40 from . import _lbfgsb
       41 from .optimize import (approx_fprime, MemoizeJac, OptimizeResult,
       42                        _check_unknown_options, wrap_function,
  
  ImportError: cannot import name _lbfgs
  

  This last line (ImportError: cannot import name _lbfgs) also occurs for importing packages from psychopy such as visual or tools,
• Roelof

  June 2018

  Perhaps also of importance: the error occurs only on a specific desktop, the same standalone opensesame version (ran from usb) works fine on my own laptop
• sebastiaan

  June 2018

  Hi Roelof,

  That's a strange error. Two things come to mind:

  • Something corrupted your Python environment. Downloading OpenSesame again and seeing if the problem persists would be a good check.
  • The lbfgsb uses some functionality that is not supported by your system. If so, then upgrading or downgrading scipy might resolve the issue. But it's groping in the dark, because it's unclear where the issue originates from.

  Cheers!
  Sebastiaan

  
  
  Check out SigmundAI.eu for our OpenSesame AI assistant!
  
• Roelof

  June 2018

  Hi Sebastian,
  Thanks for the advice, I tried upgrading scipy to version 0.12 or version .19, but to no avail.
  I did discover that python was executing in 64 bit, which I changed to 32, but it did not solved the problem, although the systems on which the same standalone version was working was 32 bit as well.

  Furthermore when scipy is not installed in my standard python folder ('C:\Python27') I get the following error:
  DLL load failed: The specified procedure could not be found.

  If I install scipy, I get the following:
  "cache deserialization failed"
  

  and then in opensesame we are back to the lgbsf error:
  cannot import name _lbfgsb

  This seems at least as if opensesame is looking for scipy package in the C:\Python27 folder, which might not be desireable, not sure how to change the priority for where to look for packages though

  When I completely remove my local python installation, opensesame also does not run psychopy and says:
  DLL load failed: %1 is not a valid Win32 application.

  Not sure if this is any help, I'll keep looking what the issue might be,

  Roelof

  Python 2.7.12
  
  * Type "help()", "copyright()", "credits()" or "license()" for more information.
  * Use the "print([msg])" function in inline_script items to print to this debug window.
  * Inspect inline_script variables when an experiment is finished.
  
  import psychopy
  
  from scipy import optimize
  
  ImportErrorTraceback (most recent call last)
  <ipython-input-2-b32e70e68d77> in <module>()
  ----> 1 from scipy import optimize
  
  C:\Program Files (x86)\_PortableOpenSesameS\opensesame_3.1.9-py2.7-win32-1\lib\site-packages\scipy\__init__.py in <module>()
      117     del _NumpyVersion
      118 
  --> 119     from scipy._lib._ccallback import LowLevelCallable
      120 
      121     from scipy._lib._testutils import PytestTester
  
  C:\Program Files (x86)\_PortableOpenSesameS\opensesame_3.1.9-py2.7-win32-1\lib\site-packages\scipy\_lib\_ccallback.py in <module>()
  ----> 1 from . import _ccallback_c
        2 
        3 import ctypes
        4 
        5 PyCFuncPtr = ctypes.CFUNCTYPE(ctypes.c_void_p).__bases__[0]
  
  ImportError: DLL load failed: %1 is not a valid Win32 application.
  
• sebastiaan

  June 2018

  Hi Roelof,

  This is going to be tricky to resolve, but it will be helpful to know the following: Python environments are completely separate, and don't share libraries, except in two cases (that I can think of):

  • When you have the PYTHON_PATH set as an environment variable. In that case, the Python path will be used by all Python environments.
  • When Python libraries use a dll that is not in the Python environment per se, but somewhere else in the system.

  I don't know if either of these is going on in your case. The fact that removing your local installation has any effect on OpenSesame at all (which is odd) suggests that it may be.

  Cheers,
  Sebastiaan

  
  
  Check out SigmundAI.eu for our OpenSesame AI assistant!
  
• Roelof

  December 2018

  update:
  when upgrading scipy to latest version (1.1.0) the experiment runs psycho backend fine, in both opensesame versions 3.1.9 and 3.2.5, the exact change that lead to the solution is still obscure, but it is working atm