Issue with blocks and looping, selecting images from 2 files randomly

OS (e.g. Win11):
PsychoPy version (v2021.2.3):

Trying to show images of faces and objects in two separate blocks, and have it loop 5 times. So the experiment would start with a block of faces, then a block of objects, then a block of faces, and so on until each block is shown 5 times. I also need the images to be selected randomly with repitition for an n-back task.

I’ve used a bit of code and a few excel files to try to make it work. I’ve hit a few errors but have worked through them a few times, I’ve gotten to the point that I have it working to loop through each block one time, but then it stops and when I set nReps to 5 in either my inner or outter loop I get an error.


Here is the code that I used:

from numpy.random import choice

blocks = [‘facestimlocalizer.xlsx’,‘objectstimlocalizer.xlsx’]
shuffle(blocks)

In the select rows for the trial handler you’ll see that I have it set to 3 right now, that’s just for testing purposes to cut down the time it takes to run the blocks.

This is the error message I get:

IndexError: list index out of range

Experiment ended.

Does anyone know what I may be doing wrong here or how I could try to fix this? Please let me know if anything is unclear. Thank you!