Altering the condition file at the start of the experiment for each participant

[TimCottier]

PsychoPy version 2024.2.4

What are you trying to achieve?:
Hi all, I was wondering if I can alter the condition file uniquely for each participant at the start of the experiment? To elaborate on what I want to do, I have a condition file that contains 280 trials that I want all participants to complete. I then have two lists with approximately 1000 possible trials, and for each participant, at the start of the experiment, I want to randomly sample 140 unique trials from each list. So that each participant completes 280 trials specified in the condition file, and 280 unique randomly selected trials.

I imagine that one way to do this, is to just generate multiple condition files offline that contain the full 560 sets of trials I want participants to do. However, I was just wondering if there was a way I can use code to avoid generating multiple condition files.

Many thanks in advance for any help provided :)!

[wakecarter]

Wakefield's Daily Tips

Avoid multiple spreadsheets One way of counterbalancing blocks in an experiment is to have an outer loop which points to a spreadsheet which contains the names of different spreadsheets to use in an inner loop. The main issue with this is that if you have multiple spreadsheets with the same columns and you want to make a change, you have to make it to all of them. The other more minor issue is that you may have to specify the spreadsheets as additional resources in Experiment Settings / Online. …

[TimCottier]

Thank you for sharing this Wakefield! An absolutely elegant and simple solution! Thank you so much!