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Psychopy: Call a conditions file from the outer loop's conditions file

I am a bit new to PsychoPy and Python coding, so please excuse my question if it is basic. In my task, I have a number of files that dictate the position of stimuli. My outer loop has a variable, ExcelList, which has the previously mentioned file names listed under it. The inner loop, which dictates each trial, attempts to call these files at random by entering $ExcelList into the space asking for a conditions file. As I understand it, the command for $ExcelList should access the conditions file in the outer loop and pull one of the files containing stimuli positions for that trial. However, I am instead presented with the following error:

File "/Users/bencline/Desktop/Psychexp/NegPriming2080_lastrun.py", line 247, in module> trialList=data.importConditions(ExcelList), File "/Applications/PsychoPy2.app/Contents/Resources/lib/python2.7/psychopy/data.py", line 1366, in importConditions raise ImportError('Conditions file not found: %s' %os.path.abspath(fileName)) ImportError: Conditions file not found: /Users/bencline/Desktop/Psychexp/Trials_20_95.xlsx

It would appear that the inner loop is not finding the condition in the outer loop (or not reading the outer loop altogether). If I try instead writing $eval(ExcelList) I am presented with the following error:

File "/Users/bencline/Desktop/Psychexp/NegPriming2080_lastrun.py", line 247, in trialList=data.importConditions(eval(ExcelList)), File "", line 1, in NameError: name 'Trials_20_95' is not defined

This seems more indicative of the underlying problem, but I'm still not sure how to proceed from here. Do you have any suggestions for why this is happening and how I could potentially fix it?

Thank you,

-Ben

Solution

  • Your strategy is right. It reads your ExcelList in the outer loop but fails to find the filenames in ExcelList on your filesystem. In particular, in your first error message, it fails to find /Users/bencline/Desktop/Psychexp/Trials_20_95.xlsx. So check whether it actually exists. I strongly suspect that it does not because of one or both of these:

    • It is in a different folder, e.g. a subfolder. The solution is to write out the path (relative or absolute) in the ExcelList file.
    • It is spelled differently, e.g. with a small T or capital postfix (XLSX), a spacebar or the like. The solution is of course to make the filenames in the ExcelList and the actual filenames match.