topic Re: Need string minus last 2 characters in Splunk Search

Need string minus last 2 characters

rachelneal — Thu, 13 Oct 2011 17:07:36 GMT

I am trying to set a field to the value of a string without the last 2 digits. For example:

Hotel=297654 from 29765423
Hotel=36345 from 3624502

I tried rtrim but docs say you must know the exact string you're removing, mine are different every time. I also tried substr but the length is not constant from 1st character and using -2 like substr(Field, -2) returns the last 2 characters...the part I want to throw away.

Was trying something like rtrim(Field,substr(Field,-2) but can't get that to work.

Suggestions? - THANKS

Re: Need string minus last 2 characters

_d_ — Thu, 13 Oct 2011 17:32:17 GMT

Hi RachelNeal,

You can extract another field and do something like this:

<your_search_here> | rex field=myfield "(?<myfield>.*).{2}"

This would drop off the last two chars of myfield.

Re: Need string minus last 2 characters

_d_ — Thu, 13 Oct 2011 17:43:19 GMT

Or another way:

<your_search_here> | eval myfield = substr(myfield, 1, len(myfield)-2)

-
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Re: Need string minus last 2 characters

rachelneal — Thu, 13 Oct 2011 17:56:18 GMT

Thanks d

Out of curiosity, do you know why "eval Hotel=rtrim(Hotel,substr(Hotel,-2)) " where Hotel was 29272905 returned 2.92729e04?

Re: Need string minus last 2 characters

_d_ — Thu, 13 Oct 2011 18:20:00 GMT

Yup, just tested it and you're right. It appears that this is happening with numbers only. Probably it has to do with arithmetic routines. I'll do some further investigation and perhaps touch base with engineering. Thanks.

Re: Need string minus last 2 characters

_d_ — Fri, 14 Oct 2011 20:48:48 GMT

Hi Rachel,
Using substr(myfield, 1, len(myfield)-2) is your best bet here. It turns out that rtrim will remove ALL matching characters that you supply:
ex. if a=201145454545 and you do b=rtrim(a, "45") b will end being: 2011. Also, sometimes Splunk will use scientific notation after a certain number length.

Re: Need string minus last 2 characters

trijit — Thu, 03 Dec 2015 15:31:02 GMT

Can we do it the reverse way like:

string minus first 2 characters ?