Hi,
I have a question A1 which is an array. Then, I have another array A2, where I should show only those questions that got answer == 1 in the previous array.

Could you give me some tips?

Thanks in advance,
Giorgio

Use subquestion relevance in the second array
like
A1_SQ001==1

Thank Joffm!
I just started using Limesurvey, so I don't know why the equation doesn't work. I also tried by using a script adding a multiple choice question but it didn't work.

You do not need a script, you do not need anything else.
Just enter the condition to show the specific subquestion into "relevance equation" of subquestion of A2.
And the equation I showed is that what you told us.

 that got answer == 1 in the previous array.

The condition of the subquestion of A2 is, that the code in A1 is equal 1.
Please, learn the basics about QCode variable naming

Please read the manual about ExpressionScript generally
and this
[url] manual.limesurvey.org/Adding_answers_or_...fic_for_subquestions [/url]

Study the sample surveys included in the manual
[url] manual.limesurvey.org/ExpressionScript_sample_surveys/en [/url]
and in the demo installation
[url] demo.limesurvey.org/index.php?r=admin [/url]

"It doesn't work" is not very useful.
Attach a lss export of these relevant question to show us what you realy did.

Joffm

Thank you very much for all the links! Now it works