Case: array question with 5-step label from "don't agree at all" to "completely agree" and, say, 6 subquestions.
I found out how to display the answers in a "text display" question type.
But how can I display only the "don't agree at all" answers?
And how can I filter out the "non applicable" answers?

www.limesurvey.org/manual/Expression_Man...e_using_placeholders

Well, you will need to write an expression that first checks the value of the answer (e.g. something like "if answer1 == 1 then write "blablabla".

OK, I understand, but I can't figure out the right syntax:

I tried
{if(Q1_sq001.shown=='don't agree at all')}{Q1_sq001.question}: {Q1_sq001.shown}
but his gives me a syntax error.

Of course, because it is not a valid EM syntax. Have a look at the examples in the manual and I think you'll figure it out.

You need to understand how the "if" loop in EM is built. Because you say "if something happens." Full stop. You closed the expression. You need to give it something to work with within {}.

Have a look at the examples here using if:

www.limesurvey.org/manual/Expression_Manager

eleren wrote: OK, I understand, but I can't figure out the right syntax:

I tried
{if(Q1_sq001.shown=='don't agree at all')}{Q1_sq001.question}: {Q1_sq001.shown}
but his gives me a syntax error.

You are Also using single quote around the to be checked text but the to be checked text contains a single quote as well. So that won't work because the quote within the text closes the expression.
In addition, the whole expression is a little wrong.

It should be like this:
{if(Q1_sq001.shown=="don't agree at all", Q1_sq001.question, Q1_sq001.shown)}

Some more notes:
1. Subquestion codes are usually like "SQ001" and not "sq001".

2. Your expression shows the question text if the answer is "don't agree..." and if not it shows the answer texts. Not sure if this is intended. Possible solution to show question text + answer text if true and nothing if false:
{if(Q1_sq001.shown=="don't agree at all", join(Q1_sq001.question, ": ", Q1_sq001.shown),"")}

Whuy using .shown ? You choice "Don't agree at all" have a code, use the code ( {if(Q1_sq001.NAOK=="NOAGR", join(Q1_sq001.question, ": ", Q1_sq001.shown),"")}