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  • Since the videos are played without hardware acceleration, 4K can indeed lead to dropped frames, I am not too surprised by this. It's a very high resolution. You might consider recoding to full HD (or try with a more powerful machine; i.e. with a mo…
  • What resolution are the videos in? On the machines I tested it on (Windows, Mac, Linux) I could play full HD videos without dropping any frames. How exactly are you showing the videos? Can you post your code?
  • Hi, easiest is to just download the zip (expyriment-master.zip) file. You install it then in the standard way to install Python packages: pip install expyriment-master.zip (assuming you are in the directory wherethat file is located).
  • Ah, now you ironically ran into another bug. This bug, however, is also fixed already, but not in the beta yet. We will release a new beta with the fix soon, but for now, you can install Expyriment directly from the repository. That should work.
  • The error is related to a bug. This has been fixed, but no official new version of Expyriment has been released yet. You can either use the development snapshot directly from the repository (github.com/expyriment/expyriment/) or you can install a…
  • Well, if you are not using the machine via remote desktop, then the problem probably is elsewhere. Maybe you can talk to the technicians at your university about this. It seems to be a machine specific issue (e.g. Windows settings, different drive…
  • Hi there, what exactly do you want to do? Since you mention MEG, it seems that you would like to send markers to the MEG system? If so, you can use the io.MarkerOutput to send markers at any point in time (e.g. right after presenting a stimulu…
  • Hi there, that is strange. One thing I noticed in your system info is that your video card is noted as "RDPDD Chained DD". I think RDPDD is usually reported when using remote desktop. Are you using remote desktop on those machines? Using remote d…
  • So from what I can see is that you are adding all 6 stimuli to the same canvas. From your description above this is not what you want... Simply creating a canvas stimulus in each trial, would solve this. #block1 block_one = expyriment.design.Blo…
  • Hi Tanto, from your post it is not clear weather this is an error in Expyriment, Trajtracker, or your code. Could you post a code example and the full traceback to the error?
  • Hi there, if you use USB triggers (keyboard emulation), then indeed you cannot use the TriggerInput, since this expects a serial or parallel port as interface. Getting all triggers without blocking the code is very tricky. You could do this in…
  • Dear tanto, the code you provided does not run. Can you post a running example?
  • Hi Randi, I thought is was solved. My code above does not work? Can you send me your code and the full traceback of the error?
  • Hi, You will need to set expyriment.control.defaults.audiosystem_sample_rate=16000 before the audio system is started (which by default is right when an experiment is initialized). Hence, put that line right after you imported Expyriment. Howe…
  • It indeed sounds like a mismatch in sampling rate between your sound file and the audio system. However, there is no such thing as "Backend Settings" or "Sampler" in Expyriment. There are two ways to fix this: * Change the sample rate of you…
  • Hi there, why don't you just call the keyboard wait method with the argument wait_for_keyup=False? Have a look at the documentation for more details: http://docs.expyriment.org/expyriment.io.Keyboard.html#expyriment.io.Keyboard.wait
  • Not sure if I understand you correctly, but wouldn't this work: def create_random_stim(): sequence = ["R"] * 27 + ["B"] expyriment.design.randomize.shuffle_list(sequence) return expyriment.stimuli.TextLine("".join(sequence)) stim1 = …
    in Prensent Stimuli Comment by fladd June 3
  • What I meant is, you put in the data manually into the data file object (usually by doing something like exp.data.add(my_data). So, since you already have the data, before you manually put it into the data file object, there is no way to get the dat…
  • Thanks for pointing me to our old changelog! I entirely forgot that we fixed this before. I was trying to fix this issue for a while now and had not clue what the issue is. I now looked up the old code and while the issue was not the same back then,…
  • Well, you have the data yourself, before you write them to the file, right? :-)
  • I am not entirely sure I understand you correctly. The getter returns the actual object itself, not the location of it. The data object is an object that is writing data to a file.
  • Hi Dror, Pygame (and hence Expyriment) is not touchscreen aware. It only knows a mouse. Usually a single touch is emulated as a mouse click (this is at least the case on Android). On your device this is apparently not the case. I assume your touc…
  • You will need to import the expyriment package, in order to use it in Python. I think at this point this forum thread might not be the best way for you to proceed. I get the impression that you might benefit more from first strengthening your gen…
  • Line 171 misses a closing parenthesis.
  • yes. florian@expyriment.org
  • I am afraid that due to automatic formatting in the forum, a lot of information is lost. You can embedd code here in the forum within three backticks on either side (Markdown syntax). Alternatively, you can upload your code to gist.github.com.
  • All of them? That is very strange. It is in general very difficult to judge errors without seeing the entire script. Could you provide the entire script?
  • Well, yes, of course. An integer is a built in Python data type representing a number, not an Expyriment stimulus. You first need to create a stimulus. Please see my example above.
  • Then I don't understand what the problem is. This should just work: mask = expyriment.stimuli.TextLine("#") target = expyriment.stimuli.Picture("...") mask.plot(target)
  • I thought prime is a stimulus you want to show on the screen?