Rookie question: 'sequence contains non-existing item'

MargrietR

Hi all!

I am a very new user of OpenSesame, since I have to use it for my master thesis. Today I did the first tutorial, so that is all I know really..

Now, I got an experiment file from another researcher that should be ready to go. It didn't work in the newest version (3.1.2) so I also downloaded the previous version (3.0.7); it now runs the experiment. However, the experiment stops at a certain point because there is a missing file. This is the message I get:

"The experiment did not finish normally for the following reason:
Could not find item 'slider', which is called by sequence item 'question_sequence'
Details:
item-stack: experiment[run].Run[run].Runseq[prepare].Randomisatie[prepare].EMsnel_sequence[run].memrating[run].rating_sequence[run].ratingquestions[run].question_sequence[prepare] "

When I go to the question-sequence in the overview, it says 'sequence contains non-existing item: slider'. I did add the files I got to the file pool (two slider.png files, a slider.py and a slider.pyc), and also put the plug-ins I got in the plugin folder.

Maybe it's a dumb question, maybe I'm not making any sense at all, but I figured I can always try! So do any of you have an idea? Any help is appreciated!

Thanks!

eduard

Hi Margriet,

the error message does not say that a file called "slider" is missing, but that an item in your experimental structure is missing. This sounds a little weird, though. Would you mind uploading the experiment, so I can have a closer look on that?

Thanks,

Eduard

sebastiaan

Hi guys,

What happened is the following:

• The slider is a plugin that was installed separately (it isn't a standard part of OpenSesame), presumably by the researcher that gave the experiment to you.
• You then opened the experiment in an OpenSesame installation in which this plugin was not installed.
• OpenSesame then gives a warning, but otherwise opens the experiment; however, in the sequence there is still a reference to the non-existing item. To fix this:
  • Edit the sequence script and remove the line with the reference to the slider; or
  • Install the slider plugin in your OpenSesame installation.

Cheers,
Sebastiaan