[solved] Controlling the randomisation of loop variables

Comments

• eduard

  July 2015 edited 8:23PM

  Hi,

  As far as I see, there is no easy and direct way of doing this with the loop item. However, doing it with an inline_script is not much harder. I would do following. First, I'd put a small inline_script in the beginning of your sequence. Furthermore, in the loop item itself, you don't have to put your variable names (A,B,C,..), but just some sort of counter.
  In the inline_script, you can put the actual part that selects the condition or item you need. Something like this, should do:

  import random
  
  # I assume earlier in the experiment you created a list with your items
  # e.g. items = ['A','B','C','D','E','F']
  # this has to be defined outside the loop, in order to make sure that no
  # item does appear more than once
  # counter can be the counter variable that is running in the `loop` item
  
  if counter == 0:
      cur_item = random.choice(['A','B','C'])
      items.remove(cur_item)
  elif counter == 5: # (or whatever the index of the last element is)
      cur_item = random.choice(['D','E','F'])
      items.remove(cur_item)
  else:
      cur_item = items.pop(0)
  
  # anything else that you want to do
  

  Does this do what you had in mind?

  Good luck,

  Eduard

  
• Xophmeister

  July 2015 edited 8:23PM

  Thanks, Eduard

  Yes, this looks like it should work Now I've learned that what is declared in inline scripts persists until the end of the experiment it should, like you say, be very easy to get things to run the way I have in mind.
• eduard

  July 2015 edited 8:23PM

  Great to hear. Then I'll mark this discussion as solved. If you happen to have more question don't hesitate to post them again in here.

  Eduard