>So, you're suggesting that I should learn Jexl so that I can divide one number by another in JMeter?
Yes you must use javascript, but its stupid simple. Javascript help on operators http://www.w3schools.com/js/js_operators.asp Functions are very simple ${__jexl(${log1ID}+1)} >Wow, that's absolutely NOT what I'd expect and I don't see that mentioned anywhere in the documentation. I came across this as well.. Basically you can't reference another variable in a UDV that was defined in that same UDV element. Things aren't ready till the end of the element. sebb added to the documentation in-progress at that point to help make that clear. >*Should* work and *does* work are totally different things. My experience with JMeter suggests that JMeter is >remarkably inconsistent as to what text fields/etc. are actually interpreted It's confusing at first, but once you know what's happening its not so bad to work with. You must live with the assumption that if jmeter doesn't understand the reference, it will just be passed as a literal string. This includes undefined variable names or syntax mismatches. Basically, instead of stopping and erroring, its going to continue and pass that as a string 'as is' rather then evaluate it. Common things I found that trip you up - case sensativity in function and variable names - the usual { vs ( typos - typos or mismatches in variable or function names People are accustomed to the program halting on syntax checking or references and jmeter simply doesn't do that. So any errors must be caught through monitoring the values being used. Only when you get invalid parameters in some of the samplers, etc do you typically get an exception at run time. The key is to use the debug sampler often when writing the script to monitor the variables and properties to ensure you are manipulating what you expect. Every time I had problems like you described, it was typically one of the above problems. The UDV issue of referencing the variable that was just defined in the same element has been the only real problem I've encounter. The rest is just coping with no syntax or reference checking... So the burden of debugging is on you. What I would like to see in jmeter though is a element that can be used just for processing expressions, etc. It seems many of the functions, etc are intended to used 'in line' vs the model of modifying variables and expressions first, then passing them into the samplers/etc. Maybe an 'executor' block :) ----- Original Message ---- From: sebb <[EMAIL PROTECTED]> To: JMeter Users List <[email protected]> Sent: Thursday, April 10, 2008 6:20:03 PM Subject: Re: Understanding How to Twiddle Values in JMeter On 11/04/2008, Dan Tripp <[EMAIL PROTECTED]> wrote: > Howdy All, > > I'm trying to perform some simple calculations with data I've extracted using an HTTP sampler and the Regular Expression Extractor. I have no problem getting the values I need/want/expect from the Regex, but I can't seem to add numbers together, and I can't seem to figure out *WHERE* the calculations should go. > > The simplest sample I've come up with looks like this: > > Test Plan > + Thread Group > - User Defined Variables > - Debug Sampler > - View Results Tree > Workbench > > In User Defined Variables, I have: > > Name Value > ====== ================================ > var1 __eval(30 + 6) __eval() does not evaluate numeric expressions. You can use intSum() for adding/subtracting numbers, otherwise use Jexl. > var2 ${__eval(30 + 6)} > var3 10 / 4 > var4 ${__eval(10 / 4)} > var5 ${__time(YMD)} > column uname > table users > sql SELECT ${column} FROM ${table} > > The output I see from the Debug Sampler is NOT what I'd expect: > > var1 = __eval(30 + 6) > var2 = ${__eval(30 + 6)} > - I was hoping to get "36" > > var3 = 10 / 4 > var4 = ${__eval(10 / 4)} > - I was hoping to get "2" > > var5 = ${__time(YMD)} > - I was hoping to get "20080410" > > column = uname > table = users > sql = SELECT ${column} FROM ${table} > I was hoping to get "SELECT uname FROM users" UDV variables are not defined until the entire element has been processed. If you put sql in a separate UDV it should work. > It may be the case that User Defined Variables is just a convenience component which makes it easier to define variables than it would be to import them from a text file and that my use of this component is wayward/errant. However, I don't know where the heck to put this stuff if this is the wrong place. > > Further, I don't seem to be able to get the expected values when I put these types of expressions in other components... UNLESS I put them in the title. The ${__time(YMD)} works great if I put it in a COMPONENT LABEL (ie.- I name that component "Today is ${__time(YMD)}" I'll see "Today is 20080410" in the results), but doesn't want to do what I'm expecting when I stick it anywhere else. That makes absolutely no sense to me. How/what am I not understanding? It should work almost anywhere. > > I'd greatly appreciate any guidance/ pointers/ references to anything that'll help me accomplish this. > > Regards, > > > - Dan > > > __________________________________________________ > Do You Yahoo!? > Tired of spam? Yahoo! Mail has the best spam protection around > http://mail.yahoo.com --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
