Presenting sets with random number of stimuli in random order

Comments

• amihai_gottlieb

  April 2016 edited 9:16PM

  Any help?

  I have done some progress and have another question: Is there a way to run less cycles than the variable levels in a loop? meaning the loop will choose randomly from the levels.
  I tried putting [a variable] in the cycles number but got an error.
• eduard

  April 2016 edited April 2016

  Hi Amihai,

  Have you already solved the randomization problem?

  Is there a way to run less cycles than the variable levels in a loop?

  Yes! In the loop item there is an advanced options checkbox. If you enable it, you can set a value for a break if field. In this field, you can add variable names.

  Does this make sense?

  Eduard

  
• amihai_gottlieb

  May 2016 edited 9:16PM

  Dear Eduard,

  I solved part of the randomization problem using loop functions.
  I was thinking to use the "less cycles than the variable levels in a loop" solution to randomize the number of stimuli from each category (although not an elegant solution..).
  Do you know how could I use the Break if check box to do this?

  And thanks for your help.

  Amihai
• eduard

  May 2016 edited 9:16PM

  Hi Amihai,

  you could use a counter variable and break the loop (with the break_if field), once the variable has a certain value. So, if you have a loop that supposed to have 15 trials, you add an inline_script to your trial_sequence, in which you increment the variable by one (counter += 1).

  Does something like that work for you?

  Good luck,

  Eduard

  btw. sorry for the late reply!

  
• amihai_gottlieb

  May 2016 edited 9:16PM

  Dear Eduard (or anyone else who can help),

  Thank you very much for your replay. I used your tip and eventually managed to find a plausible solution. Yet, now I have another problem: I need to log the pictures that were eventually presented in the loop from the total number of possible pictures. The output file does not give me this information. Is there a way to do this?

  Thanks you
  Amihai
• Josh

  May 2016 edited 9:16PM

  Hi Amihai,

  All exp.variables are automatically logged by the log item, so all you have to do is to store the picture names in a few variables.

  Say you have a picture list as follows: pictures = ['1.jpg','2.jpg','3.jpg'], shuffled with random.shuffle(pictures). Now you can log them as follows:

   exp.pic1 = pictures[0]
   exp.pic2 = pictures[1]
   exp.pic3 = pictures[2]
  

  Hope this hepls.

  Cheers,

  Josh
• amihai_gottlieb

  May 2016 edited 9:16PM

  Hi Josh,

  First of all, thank you.
  Secondly, I did not understand your answer. I am using a loop function to randomly show the pictures from a variable list with the pictures names. I have two categories of pictures so to randomly show a different proportion from each category I used the "less cycles than the variable levels in a loop" option (see above). How can I know which pictures were eventually shown?

  Amihai
• amihai_gottlieb

  June 2016 edited 9:16PM

  Still no luck.
  doed any one have an idea how to solve this?
• Josh

  June 2016 edited 9:16PM

  Hi Amihai,

  What I suggested requires the use of an inline_script item. You can place that thing somewhere in your trial sequence. I also assume that your pictures have names, right? (e.g. '1.jpg'). As soon as the picture for your trial is specified, you can log it.

  Cheers,

  Josh
• amihai_gottlieb

  June 2016 edited 9:16PM

  Hi Josh,

  I am using the sketchpad to display the images from the loop function.
  This is the text from the sketchpad script:

  set duration "[duration]"
  set description "Displays stimuli"
  draw image center=1 file="[words]" scale=1 show_if=always x=0 y=0 z_index=0

  How can i log the image from this?

  And thank you very much for your help

  Amihai