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Saving data from specific loops

Hello,
I am using the Builder to create code for an online study. I am having some difficulty parsing out the output in the resulting csv file. What Builder automatically outputs seems like a crazy amount of data and I’m not sure how to cut it down. Is there a way to indicate what specific trials/loops to save? For example, I have a set of practice trials that I don’t care about the data for, so I would like to completely remove those trials. Additionally, within the trials that I do want to save, there are columns that are unnecessary. Can I specify what info I’d like to save?

Thank you so much!

So in general the advice is not to remove data at the time of recording but after the recording (e.g. with R or with Python, cf. this post).
That being said, for loops which are not trials, there is the option to uncheck Is trials checkbox in the loop window of the builder. I haven’t tested this online, but for offline studies, these loops then don’t generate a row of data for every iteration.

My experience is that removing the isTrials tick doesn’t remove the data online

Agreed with the other response, isTrials doesn’t seem to affect online studies. I know it’s better to have data than not, but, for example, I am looping through an excel file to store text stimuli (I saw that method recommended here, but if there’s a better way, I’m open to it), so each loop adds a row of data leading to 600 extra rows. I know it’s easy to fix post-collection but I thought there might a way to avoid that. Thank you anyway for your answer!