InstantForum 2017-1 FinalMillisecond Forumshttps://forums.millisecond.com/Millisecond ForumsFri, 01 May 2026 21:00:02 GMT20https://forums.millisecond.com/Topic13447.aspxDear Community,&nbsp;<br/><br/>I am trying to use the Prospective Time Estimation task provided by Inquisit.&nbsp;<br/>Instead of just doing one trial at a fixed time interval of 53 seconds, I am trying to do multiple trials of random length.&nbsp;<div><br/></div><div>Instead of using:<div>&lt;values&gt;<div>...</div><div>/timeinterval = 5300<div>&lt;/values&gt;<div><br/></div><div>I'm using:<div>&lt;values&gt;<div>...</div><div>/timeinterval = ceil(rand(45,75))*1000<div>&lt;/values&gt;<div>To achieve a random time interval in between 45 &amp; 75 seconds.&nbsp;<div><br/></div><div>I'm currently just running two experiment blocks:<div>&lt;expt &gt;<div>/blocks = [1 = timeestimationstart, 2=<span style="font-size: 10pt;">timeestimationstart]<div>&lt;/expt&gt;<div><br/></div><div>This works except that the time interval variable isn't reassigned the second time, so my interval is the same for both trials.&nbsp;<div>I have tried to force the reevaluation of the timeinterval variable:<div>&lt;trial start&gt;<div>/stimulustimes = [0=start, circle]<div>/timeout = [values.timeinterval = ceil(rand(45, 75))*1000]<div>/branch = [trial.end]<div>/recorddata = false<div>&lt;/trial&gt;<div><div><div><br/></div>But this fails with "Expression '[values.timeinterval' is invalid. Expression contains an unknown element or property name."<br/></div>I could just hardcode a second timeinterval, a second trial and second variable to be exported but I'd prefer a more elegant solution.&nbsp;</div></div></div></div></div></div></div></div></div></div><div>It's been a while since I've coded much in Inquisit, been spending most of my time in python, js &amp; R. Thus I'm undoubtedly over thinking this, I think...</div><div><div><br/></div>The code I'm working with can be found here (the prospective task):&nbsp;<a href="http://www.millisecond.com/download/library/TimeEstimation/">http://www.millisecond.com/download/library/TimeEstimation/</a></div><div><div><br/></div>Cheers,&nbsp;<br/>Sante</div><div><br/></div><div><br/></div><div><br/></div><div><br/></div><div><br/></div></span></div></div></div></div></div></div></div></div></div></div></div></div>Tue, 03 Jun 2014 15:49:23 GMTskotturihttps://forums.millisecond.com/Topic13458.aspxGreat, that works and makes a lot more sense.&nbsp;<div>The /ontrialbegin method was just what I was looking for!<div>Cheers,&nbsp;<br/>Sante</div></div>Tue, 03 Jun 2014 15:49:23 GMTskotturihttps://forums.millisecond.com/Topic13448.aspx<div>#1:<br/></div>Values are -- by design -- static. I.e. the expression in <br/><div><div><div><br/></div>&lt;values&gt;</div><div>...</div>/timeinterval = ceil(rand(45,75))*1000<div>&lt;/values&gt;</div></div><div><br/></div>will get evaluated once and then values.timeinterval will remain unchanged. It is supposed to.<br/><div><br/></div>#2:<div>This<br/></div><div>&lt;trial start&gt;<div>...<br/><div>/timeout = [values.timeinterval = ceil(rand(45, 75))*1000]<div>...</div></div></div><div>&lt;/trial&gt;<div><div><br/></div>is simply invalid syntax. The correct way to express it would be simply<div><br/></div>&lt;trial start&gt;<div>...<br/><div>/timeout = ceil(rand(45, 75))*1000<div>...</div></div></div>&lt;/trial&gt;<div><div><br/></div>#3:<div><br/></div>The proper way to do this is<div>&lt;values&gt;<div>...</div>/timeinterval = 5300<div>&lt;/values&gt;</div></div><div><br/></div>&lt;trial start&gt;<div>...<br/><div><div>/ontrialbegin = [values.timeinterval = ceil(rand(45, 75))*1000]</div>/timeout = values.timeinterval<div>...</div></div></div>&lt;/trial&gt;</div></div></div></div>Tue, 03 Jun 2014 03:38:15 GMTDave