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I need to set up a 3-question survey for Major Choice in university, Alll question is singal choice question.
Question 1, What is your major? Answer will be 1~9
Question 2, Will you change your major? Answer is Yes or No.
Question 3 Is the future major you will choice. But it will be partially setup base on the previously answer from Q1 and Q2.

For example, if Q1 = 7 and Q2 = No, then the Q3 will automatically set to 4.

Can I make it by LS? Thanks for help!!!

What's the exact workflow?
Q3 is set to 4, but then displayed that the respondent is able to change?
Or is Q3 hidden and set to 4 in the background?

Anyway: use ExpressionScript like
{Q3=if(Q1==7 and Q2=="N",4,Q3)}
with Q2 as Y/N question..

Joffm 

I think it will be:
Q3 is set to 4, but then displayed that the respondent is not able to change.

Because other respondent may complete Q3 by choosing the option they like.


for example the if respondent choose Q1 = 1 and Q2 = Yes, respondent need to choose the Q3 by themself.

Thanks for your help, the "ExpressionScript" you mean set the question as "ExpressionScript"? Then how to keep the single choice question for others?
Thanks agian!

And little more development,
if the condition is Q1= 1~5 How to express?

I have tested the
((Q1.NAOK == "06" or Q1.NAOK == "07") and (Q2.NAOK == "N"))

It can show or hide the Q3.

But the {Q3=if(Q1==7 and Q2=="N",4,Q3)} does not work
I used {Q3=if((Q1.NAOK == "06" or Q1.NAOK == "07") and (Q2.NAOK == "N")), 04, Q3}

Of course "Q1==7" doesn't work if your code is "07".
But the thread opener talked about "7".
And nobody mentioned code "06" so far.

This is the disadvantage if you do not provide a loss export of a small sample.

Joffm

I have set the 3 question, it have set the condition for Q3 by LS file is here
 

Now two questions need to be solved

1. How to express the if the answer is 01~06 ?
2. How to make default answer by ExpressionScript? I have checked the "edit the default answers", there is no place to input the ExpressionScript.

Thanks for help!
 

Hi,
if (Q1 == '07' && Q2 == 'Y', '03', '')

This is not a condition. 
A condition is a logical term that is either TRUE or FALSE.
BTW: In your first post you wrote

if Q1 = 7 and Q2 = No, then the Q3 will automatically set to 4.

What "Yes" or "No"?
I suppose "No".
First I changed these codes "01", "02", ... to the numerical codes 1,2,3,---
So it should be
Q1!=7 OR Q2!="N"  or analogue !(Q1==7 AND Q3=="N")
Q3 is displayed if Q1 is not equal 7 or Q2 is not equal "N".
Then the respondent enters his choice.
To avoid an initial display of Q3 that is suddenly hidden, you only run the condition after Q1 and Q2 are answered.
!is_empty(Q1) and !is_empty(Q2) and (Q1 !=7 OR Q2 != 'N')

Otherwise, if Q1 is equal 7 and Q2 is equal "N", Q3 is not displayed and the value is set in the background.
Here you use an equation that assigns the value (4) to Q3.
You may read the manual about assignments.
Create a question of type equation somewhere in your survey after these three questions.
{Q3=if(Q1==7 and Q2=="N",4,Q3)}

 

Joffm

After I check the detail for the structure. I think I fianlly understood the way LS control the answer.

The Q4( final question hide Equation) can control the result of Q3. And make the file data set to what it designed. Am I right?

Many thanks, really help me to understood how LS works.