I'd like to auto-tick multiple-choice answer based on a previous answer.

For example

Question q1: Select your documents

> Subquestion a: Document A [ ]
> Subquestion b: Document B [ ]
> Subquestion c: Document C [X]

i.e. User selects Document C

Question q2: Select your documents

> Subquestion d: Document D
> Subquestion e: Document E
> Subquestion f: Document C [X]

i.e. User doens't need to select another time Document C, it is auto-selected.

I tried using relevance equation for Subquestion f as it follows:

but this code only hide the question.

The relevance equation is only there for hiding/showing questions.

What you will probably have to do is create a hidden equation type question, check if a subquestion has been checked and then mark it.

Probalby something like this (not tested, and you will of course have to make adaptation to fit for your survey):
Something like that.

holch wrote: Probalby something like this (not tested, and you will of course have to make adaptation to fit for your survey):

Code:

{if(q1_c=="Y", q2_f="Y",)

Something like that.

No, it never work.

Asignation must be done like this:
{q2_f=if(q1_c=="Y", "Y","")}

{QuestionToAssign=ValueToSet}

Not in other way

No, it never work.

I noticed that. I played around a little, and it did not work.

Thanks for skipping in and proposing the correct way.

holch wrote: …

Thanks for skipping in and proposing the correct way.

Thanks to you for all community help you offer gracefully

But somehow your solution didn't work for me either.

I assumed it works only if the second question is on a different page, but it didn't.

Do you see any errors?

holch wrote: …

I assumed it works only if the second question is on a different page, but it didn't.
…

Yes : assign action is done only with PHP, then when move next /previous

In same page : you can have a look at this old javascript code : demonstration.sondages.pro/676785?lang=fr

survey in french, but code is international

MULTIPLE : updated via js (to trigger filter on FILTER and FILTEREXCLUDE)

MULTIPLE2 : updated via php (to trigger filter on FILTER2 and FILTEREXCLUDE2)

Think the system still work on 3.X.
If PHP system didn't work : it's a bug

Hi Denis, thank you for your answer.

I'm using Version 3.14.10+180924. I tried your code this way

{q2_f=if(q1_c=="Y", "Y","")}

and I also tried

{q2_f=if(q1_c=="Y", "Y","N")}

However, it didn't work.

I also saw your demo here demonstration.sondages.pro/676785?lang=fr , however it seems this example is using array questions.

However, in my survey we are using simple multiple choice questions. Maybe that's the issue here.

@develnick, your first equation is correct but the assignment needs to be done in an equation type question, not in a long-text as you have for "G1Q3".

Working sample survey attached:

This was actually my example (thus my error!). I don't know how this could happen. Must have clicked wrong at one point. I even wondered what that stupid box was in the equation question...

I guess I know now. I need the weekend.

Tried to change it, but it won't change??? Strange. Need to check if this is a bug.

Works! Thank you Tpartner for highlighting this stupid mistake with the wrong question type. I was looking and looking and looking and didn't see what was wrong with my code. Turns out: Nothing.

Thanks, your explanation is great.
What about if the user wants to change also the Q1_c answer while choosing Q2_f i.e. one-to-one correspondence? For instance, imagine an user de-tick Q2_f. With your code, Q1_c is still selected.

Maybe I can try

{q1_c=if(q2_f=="Y", "Y","")} but where do I have to put that code?