Conditional+Looping Timelines

[ritu9901]

Hello,
I am trying to create an experiment where the timeline is dependent on the last_trial_data_response.

        var looping_pgs = {
            timeline: [pgs],
            loop_function: function(data) {
                if(jsPsych.pluginAPI.compareKeys(jsPsych.data.getLastTrialData().values()[0].response.name[0],
                'i don't want to answer'){
                return false;
                } else {
                    if(jsPsych.data.getLastTrialData().values()[0].response.name.length===1){
                        console.log('single-parameter-func/page');
                        return true;
                    }
                    else if(jsPsych.data.getLastTrialData().values()[0].response.name.length>1){
                        console.log('multi-parameters-func/page');
                        return true;
                    }
                    else{
                    return false;
                    }
                }    
            }
        }

In place of console.log('single-parameter-func/page'); and console.log('multi-parameters-func/page');, I want to display another trial and as soon as that trial gets over, the loop should continue from where it left.

additional details:
trial pgs is survey-multi-select
jsPsych.data.getLastTrialData().values()[0].response.name is an array
experiment begins conditionally.

Thanks in advance for any help! I hope I did describe everything precisely enough.
And keep up the very good work! jsPsych is super useful :)

[becky-gilbert]

Hi @ritu9901, I think what you need to do is move the logic from the else block into a conditional node, which will go in your loop timeline after pgs. So your looping timeline will be something like [pgs, new_trial_conditional]. Then on each iteration of the loop, the pgs trial will run, then the conditional node will determine whether the additional trial should run or not before the loop continues.

Also, I don't think you want to use the compareKeys function in your if statement - see my comment about that here.

I hope this helps! Let us know if you need more guidance.

[ritu9901]

Hi @becky-gilbert, thank you for getting back to me. I tried what you are suggesting as well, but the problem with this approach is that value of jsPsych.data.getLastTrialData().values()[0].response gets changed and hence it creates an error.
I tried working with jsPsych.data.get().filter({exp_name: 'pgs'}).values(). If there is any way that I could get last response using filter method, I think the problem would be solved.

Also, I really appreciate your tip for not using compareKeys for such tasks. Thanks :)

[becky-gilbert]

Hi @ritu9901, hmm, I'm not sure why getLastTrialData doesn't work in the conditional function, because the conditional function should always run after a pgs trial. Maybe you could share your code?

In any case, you can use the filter method instead. To get the last trial data you can call the jsPsych last function on the data collection that you get after filtering, before returning the values.

var last_pgs_trial = jsPsych.data.get().filter({exp_name: 'pgs'}).last(1).values();

Does that work?

[ritu9901]

heyy @becky-gilbert !
I am sorry for the delay in response.
var last_pgs_trial = jsPsych.data.get().filter({exp_name: 'pgs'}).last(1).values(); worked perfectly!!
Thank you so much.
And, happy new year!! sending love and power :))