Hi there,
I’m trying to do what I believe is a simple thing but am struggling as a fairly new PsychoPy user. I’m trying to get two circle stimuli to randomly present either on the left or right hand side of the screen between trials. In builder I have a yellow circle stimuli set and a blue circle stimuli. I’ve seen a solution where an excel sheet is fed into a loop which sets the position. The loop is set then to random so the circles either present on the left or right and this changes between trials.
Currently, the circles aren’t switching position at all.
In each circle stimuli I have the following code in the position field: [yellow_x_pos, 0] in the yellow circle and [blue_x_pos, 0] in the blue circle.
In the spreadsheet I have the following:
blue_x_pos |
yellow_x_pos |
-0.5 |
0.5 |
0.5 |
-0.5 |
-0.5 |
0.5 |
0.5 |
-0.5 |
Thank you. 
Dear Charlotte,
If you look at where you put the image position in the builder, you’ll see beside the field a drop-down box with “constant” selected. Change that to “set every repeat”, so that every repetition it changes what values to use.
Lemme know if that works!
Issac
thanks for the speedy reply. The position field is set to ‘set every repeat’ for both stimuli already so I’m very foxed as I thought this was the answer!
Could you provide a copy of your excel file and experiment for me to look at? I can’t really see the images too well.
positions.xlsx (8.9 KB)
Study_1_Reward_Learning_Task_OST_debug.psyexp (327.6 KB)
Hi Santley1O1,
thank you for looking at this for me - spreadsheet and experiment file are uploaded 
I think you are missing some excel files. However, I am not sure why you have the practice_block loop. You only do that once, so its set up to display the circles 5 times, then do the fixation, feedback, and rating. Whereas your main trials don’t have that loop in the “choice” routine. So each trial shows the choice once, and then goes through the post-stimuli stuff and repeats that 5 times.
Have you checked to see if this experiment works in the main experiment trials?