How to random a chart?

I am trying to use matlab code to random a word chart. I want to random one line of the chart, not a single word. But I've checked the function like random (line 1: line 15), didn't find an appropiate code. Anyone could help on this? thanks.

[Mohammad Sami]

Would you be able to clarify your questions ? Perhaps you can give an example of what you are trying to do.

[Dorris Yan]

I am doing a 1-back task. I want to use the stimulus below. So this makes me need to random one line of these stimuli. Every stimulus will appear 5 times and once as a target. I got the idea of randon each single word by using code. But what if I want to random the work with other features, what should I do? Thank you for the help.

Answer 1

[Adam Danz]

Use random permutations.

Apply this example to your data.

words = ["A" "B" "C" "D" "E" "F" "G" "H"];
randIndex = randperm(numel(words)); 
words_randomized = words(randIndex); 

[Dorris Yan]

Just check. Do you mean first define each stimuli and its features as A B C...and then use word random function?

[Adam Danz]

No, this is just an example of how to use randperm. You can apply this method to your data.

I don't understand how you'd like to randomize your table. If you can explain it again, I could help you apply this method to your data.

[Dorris Yan]

I want to conduct a 1-back task with the subjects pressing a button for immediate stimulus repetitions. All the stimulus are presented in a pseudo-random order. There are ten stimulus. Each one will be presented four times as non-targets in separate blocks segregated by stimulus type. In addition, each stimulus appeared once as a target. 4 catch trials will be presented as well to keep participants' attention.

Above is my task explanation. Can you please help with this? Thank you very much.

[Adam Danz]

What section of that would you like help with?

If you don't know where to start, break it up into smaller steps.

[Dorris Yan]

Actually I will conduct the task via E-prime, but I have no idea of the random procedure. I've see some random function for letter and number. Can you please help? or give me some clues. Thanks.

words = 'droad, stoad, shreaf, gleaf, nasp, shasp, lorn, vorn, noad, shoad' % the words stimuli I want to use
A = words
picture = "pic1, pic2, pic 3, pic4" % the catch trial I would use
B = picture
stimuli = A + B % all the stimuli
sequence = char(ones(27, 2)); %there will be 2 blocks (5 times for each words, 1 as target), so it would be 27 X 2 char array

[Adam Danz]

It's been a dozen or so years since I've set up an e-prime experiment. I've used cpp to set up and control experiments since there. So, if you're looking for help with e-prime you'll likely need to look elsewhere.

If you're trying to set up the conditions in Matlab, I can help you there but first you'll need to clearly define the specific problem you're tying to solve. For example, I have these variables [...] and am trying to do this specific action with the variables [...].