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trial limit
Hi FF team,
I'm getting an error that my blocks are exceeding the number of trials allowed. The message says i have 329 trials when only 150 are allowed, but i'm not sure how this is calculated, because i thought i had only 36 trials per block...? I assume this has to do with the following piece of code, as 36 trials times 9 trial templates per trial is 324 (and then some additional cover and end trials i guess). The reason why i have so many "BS" templates is because when i was using durations of stimuli vs trials to get a blank screen this was messing with the trials proceeding properly and so adding a blank screen in between instead worked much better.
"BL1": {
          "trial_templates": ["BS","Vprime1","BS", "prime1","BS", "Vtarget1","BS", "target1", "catch"],
          "pattern": {"order": "alternate_random"},
          "fetching_point": true,
          "cover_trials": ["fixation"],
          "end_trials": ["break"]
The issue is this means i'll have to more than half the amount of actual trials i have per block, which i really would rather not do and so i was wondering if this trial limit is something that can potentially be increased? 

Hi Bissera,

Inside the block BL1, you can add:

max_trials: 400

where 400 is the max number of allowed trials. We keep this feature on a need-to-know basis because you can easily imagine one may accidentally build a study with 1000+ trials in a block, and that may crash FF servers entirely. So use this feature responsibly please? Smile Thanks!
Hi Ting,

Thanks a lot! I will use only when really necessary, i can imagine the mess no limits could create...

You are most welcome, Bissera!

For everyone else reading this, we'll cap this parameter at 500 in early May, meaning that 500 trials will be a hard upper limit per block. Smile

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