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Find difference between numerical values in a Multivalue field

jaysonpryde
Path Finder

Hi,

As mentioned in the subject, I wanted to perform a simple subtraction operation on individual values/elements within a multivalue field.  So for example, I have a MV

23
79
45
23
38


I will iterate over the items, and perform the subtraction to get the following:

Iteration 1diff = 0 (since it's the first element)
Iteration 2diff = abs(79 - 23)
Iteration 3diff = abs(45 - 79)
Iteration 4diff = abs(23 - 45)
Iteration 5diff = abs(38 - 23)

 

So far, here's what I did:

| makeresults
| eval a1="23,79,45,23,29"
| makemv delim="," a1
| mvexpand a1
| eval start=0
| eval i=0
| foreach a1
  [
    eval tmp='<<FIELD>>'
    | eval diff=if(start==0, 0, "subtract_element[i+1]_with_subtract_element[i]")
    | eval i=i+1
    | eval start=1
  ]

dummy querydummy query

I haven't implemented the subtraction logic yet, since obviously, I am having a challenging time in doing it. I've spent almost 3 hours already experimenting, but no luck.

Another weird thing (for me), which I can't explain, why the variable "i" is not incrementing even if I'm updating it within the foreach block.

Hope my question makes sense, and as usual, thank you very much in advance.

Any ideas are greatly appreciated

Labels (1)
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1 Solution

kamlesh_vaghela
SplunkTrust
SplunkTrust

@jaysonpryde 

Is this you are looking for?

| makeresults
| eval a1="23,79,45,23,29"
| makemv delim="," a1
| mvexpand a1
| autoregress p=1 a1 | eval diff=abs(a1-a1_p1)

View solution in original post

kamlesh_vaghela
SplunkTrust
SplunkTrust

@jaysonpryde 

Is this you are looking for?

| makeresults
| eval a1="23,79,45,23,29"
| makemv delim="," a1
| mvexpand a1
| autoregress p=1 a1 | eval diff=abs(a1-a1_p1)

jaysonpryde
Path Finder

Hi @kamlesh_vaghela , Thank you very much for the reply.

And yes, that's what I am looking for. I just added a :

| fillnull value=0 diff

to set 0 for the first element.

Thanks again! 

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