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Selecting a single stimulus from a list without repetition

Hello! I am using PsychoPy version 3.1.2 to create an experiment about smell and emotion. I am brand new to PsychoPy and cannot figure out how to get the program to randomly select a single stimulus from my conditions file per execution of the loop. My conditions file looks like this:


At the moment it is presenting all of the stimuli in the file for every execution of the loop. I would like it to randomly select 1, then repeat this 32 times without ever repeating the same stimulus. I have another routine later in the experiment with the same procedure, and I would also like to avoid repeating any of the stimuli used in the first routine. Apologies if I am using the incorrect terminology.

I have no experience coding, so any help would be appreciated!

Hi @hannahkelson, the trial handler already provides randomisation without replacement. You can use the “random” option to achieve this. As you want to present only 32 stimuli from your conditions list, do you mean that you have more than 32 rows in your conditions file, and you want only 32 of those rows to be selected at random?

Thank you so much for your reply! Yes, I will have 200 rows in my conditions file but I only want it to select 32 of them at random. Then later in the experiment I would like it to select a different 32. How do I prevent if from presenting all of them?