Randomizing different sets of videos (which are shown in a partly-fixed-partly-randomized order)

OS: Win7 (64 bit)
PsychoPy version: PsychoPy3 2020.2.5
Standard Standalone?**: Yes

Hi all,

I am new to PsychoPy and also hopeless at coding. I would really appreciate your help regarding the following problem:

I wish to design an experiment involving 20 sets of video clips. There are 4 clips per set (called Clips a, b, c, and d). In each set, Clip a is always to be shown first, while Clips b, c and d are to be shown randomly afterwards. After a set is presented completely, another set of clips (say, 6a, 6b, 6c, and 6d) will be randomly selected and presented in the same fashion. For a more straightforward impression, please see this file. 20 video sets.xlsx (10.8 KB)

My impression is that I need to create two loops to achieve this - an inner loop randomizing Clips b, c, and d within each set, and an outer loop randomizing the 20 sets of clips. The problem is I don’t really know how to set the parameters…

Alternatively, would it be better to collapse Clips a, b, c, and d within one single routine and set up a ‘random seed’ for the displaying of each set of clips? If yes, how can I do this?

I know these are a lot of questions! I really appreciate your time, and many thanks in advance!

All the best,
Xinyan