# Equations based on an Equation

3 years 8 months ago #119952 by jazzy
jazzy created the topic: Equations based on an Equation
Hello LimeSurvey World!

I have several arrays that I'm using equations to calculate their score. So let's say I have 3 arrays and the 3 equations, one equation after each array. This part works great! No Problems. But, can I use another equation to add them all up?

For instance the 3 equation fields are array1score, array2score, array3score. Can I have a last equation be the sum of the 3.

Total Score: {sum(array1score.value,array2score.value,array3score.value)}

So far it doesn't work for me. Keeps returning 0 even though each has a number showing. Wondering if the value isn't there until it's written to the database. I've also used the array1score.NAOK and it also didn't work.

Thanks for any help!

3 years 8 months ago #119954 by Bigred01
Bigred01 replied the topic: Equations based on an Equation
I just did a quick test and when i used .value on an array row, it always returned 0. Try using .NAOK, that worked for me.

In my working test I had 1 array and 3 equations. First equation had {array_1.NAOK}, second equation had {array_2.NAOK} and third had {sum(eq1.NAOK,eq2.NAOK)}.

3 years 8 months ago #119963 by jazzy
jazzy replied the topic: Equations based on an Equation
Thanks Bigred. I tried that but so far I feel like I'm just hitting my head against the wall and hoping for a different outcome

I've attached a small sample survey to showcase my lack of understanding of this problem. If anyone can point me in the right direction to the promise land I would be much appreciative.

#### File Attachment:

File Name: array_test.lss
File Size:22 KB
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3 years 8 months ago - 3 years 8 months ago #119964 by Bigred01
Bigred01 replied the topic: Equations based on an Equation
I don't think you can access the assessment value in the survey (someone please correct me if im wrong).

Here is an example of what you can do though.

{sum(if(array1_SQ001.NAOK == "4",-1,array1_SQ001.NAOK),if(array1_SQ002.NAOK == "4",-1,array1_SQ002.NAOK),if(array1_SQ003.NAOK == "4",-1,array1_SQ003.NAOK))}

Set the answer code to the number value you want. Of course we cant set a code to -1, but the if statement above will change a 4 into a -1 when summing your answers.

Also, you have text in your equations making them strings so you final sum wouldn't have worked.

Remove the text and modify the above sum/if statements for your first two equation questions then sum them together in your final equation question.

I attached an updated copy of the survey as well.
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Last Edit: 3 years 8 months ago by Bigred01. Reason: sub to sum
The following user(s) said Thank You: jazzy

3 years 8 months ago #119968 by jazzy
jazzy replied the topic: Equations based on an Equation
You Rock! I was putting text in the fields and trying to do calculations with it. In my head I thought it was just saving everything after the colon and the before part was just for show.

Thank You!!