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Creating Variables dependent on other variables

T-J-LT-J-L Posts: 3
edited September 25 in OpenSesame

Hello everyone :smile:

I am currently designing an eye-tracking experiment for emotion recognition with OpenSesame 3.1.9b1.
To collect the answers, I used the built-in form for multiple choice answers.
According to my what I read on here, there is no way to indicate the correct response in the forms, right?
And also, there is no easy way to let the 'form_response' give out numbers instead of the respective strings, right?

I am very new to programming, and just started learning python to accomplish what I want.
So I tried to define a new variable with an inline_script-item after the form and before the logger.
I managed to create the variable, and it also prints some values to the log-file.
I want the variable to print 1 if "correct_response" and "response" are the same (strings) and 0 if otherwise.

(The definition for the correct response was done in the loop table with the variable correct_response, in case you wondered.)

While testing, it only prints a 0 to the file, with an occasional 1 now and then.
The 1, however, does not turn up when the answer was right, but seems to appear randomly, also with wrong answers.
So I suppose there is something wrong with my code, or the code cannot access the variables in the way I want it to...

The code I used is the following:

def emotion_recognized ():
    print self.get('emotion_recognized')
emotion_recognized = ()
if var.get('response') == var.get('correct_response'):
        emotion_recognized = 1
        emotion_recognized = 0
var.set('emotion_recognized', emotion_recognized)

I would be really happy if anyone could help me resolve this, somehow!
Have a good start into the new week.

Best wishes from Switzerland and thank you very much in advance


  • T-J-LT-J-L Posts: 3

    When I put the code in the run, not the prepare window of the inline_script, it seems to work just fine now!

    But another question came up:
    How can I sum the values in the variable emotion_recognized to a variable called sum_correct?
    I get an iteration error when I try to do so. It would be great to just do the same procedure, the correct response Item of the feedback does...

    Any help appreciated!
    Thanks and best wishes

  • eduardeduard Posts: 889

    Hi Tim,

    Initialize sum_correct somewhere in the beginning of your experiment (or your block). Then every time you want to update it you just add emotion_recognized to it: sum_correct += emotion_recognized. If you want to use them in the feedback item, you should use var.sum_correct instead.

    Good luck,


  • T-J-LT-J-L Posts: 3
    edited September 27

    Dear Eduard

    Thank you so much for your answer!
    If I put the var.sum_correct += emotion_recognized it simply gives the same values as in emotion_recognized, not the sum of correct trials.
    I inserted the code in the Script right after the Multiple Choice Form that gives the value to emotion_recognized.
    The sum_correct is initialized at the beginning of the experiment (right after the welcome page).

    Where's my mistake? :/
    Best wishes

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