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Expyriment test suite on OpenSesame

edited May 2016 in OpenSesame


I'd like to know why the visual timing accuracy measured by Expyriment test suite on OpenSesame is bad.

I use OpenSesame with Expyriment on MacOS.
While Expyriment test suite shows good visual timing accuracy, Expyriment on OpenSesame (i.e., I run the test suite in Inline code) doesn't show.
It seems that OpenSesame doesn't use the back-end of Expyriment even though I set the Expyriment back-end.
When I use the Pygame back-end on OpenSesame and run the test suite, the timing gets accurate.

What is the cause of this?


  • edited 8:52AM

    Hi rrr,

    That is interesting news, but we need more information to search for a probable cause. OpenSesame really uses the expyriment if you set it as the backend to use, so the cause of this problem should likely be searched somewhere else. When do you find the bad timings? Is it in the response recordings, the stimulus presentations (I assume that's what you mean with visual timing), or the inter-trial intervals? Can you report which version of OpenSesame and expyriment you are using by typing


    in the debug window and posting those results here? Additionally, it would be of use to post the differences in results of the timing tests between opensesame and standalone expyriment here to. All that will help us to get to the bottom of things.

  • rrrrrr
    edited May 2016

    Hi dschreij,

    Thank you for your reply.

    We use OpenSesame 3.0.7, Python 2.7.11, and Expyriment 0.8.0 on Macbookpro (OS10.10.5).

    Here are three results of test suite. First is the result that we run the Expyriment test suite in inline code of OpenSesame using Expyriment back-end. Second one is that we run the Expyriment test suite in inline code of OpenSesame using legacy (pygame) back-end. Last one is the result of Expyriment standalone.




    We only run the script below.

    from expyriment import control

    control.defaults.open_gl = 3


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