Grampa_of_Oliva_n_Eden

... I would be a bit surprised if you had engineers in architect roles that didn't know how to architect OO patterns...

If LV architects have to be familiar with the OO paterns then I don't qualify.

That would suit me just fine because then I would be able to charge off my time at half the rate and have twice as long to do the work.

Besides, is would save me the trouble of breaking out my buisness card everytime I have to spell the word "architect".

Back to the topic of AE vs LVOOP

One difference we did not touch on is that LVOOP places a requirement on the code that uses it that it must carry the LVOOP wires around. Yes the wire is flexible, but it still has to be there. AE encapsulate the wire so ripping an AE out of an app just requires deleting the AE or its wqrapper. To toss a LVOOP wire you have to run the track ball farther.

Ben

This is an excellent idea... I had not thought of that.

...

That's very cool. I hadn't seen it. I know FG's are very fast so if raw speed is a concern that might be a better route to go than holding the data in the class cluster. I do wonder what the performance change would be if the AE (but not the FG) were refactored into a class.

Re: Excellent idea

All credit goes to Jim Kring for teaching me that.

Re:speed

I have a wall full of customer thank you letters that read like "... you have done what NI said could not be done!". Most of that was earned on the back of AE's.

I have devloped two shipped LVOOP apps, both of which met the customer needs and the second actually gave me some re-use fodder (the first was a "Create Controls on the Fly" app so I have to wait for the next time wants that functionality to re-use it). From what I can tell, LVOOP could certainly rival most AE implementations. I don't know about those apps that have a large RT data set and just that one value needs decremented... provided we don't use accessors to read it and write it back (Q about if can work inplace in the original class buffer). I guess if i wait long enough I'll answer Q for myself.

Sorry but I used up my quota of pluses for today.

Ben

The "anti-pattern" topic is a good one if LVOOP is concidered a Pattern since the two approach are alomst the other inside-out. It takes a bit of a pradigm shift to move from one form to the other since in the AE the data is right thre is the SR staring at you. THe LVOOP version is touching data that is not here (at least as it appears from the diagram view of the method).

Ben

Recently there have been a few discussions about action engines as they relate to specific applications (here and here) but the topic is broad enough that I felt it deserves it's own thread.

Ben, you left out part of the definition...

AE= Action Engine >>> loosly a Functional Global Variable and a commonly used Labview anti-pattern.

<---Disclaimer--->

Ben, these comments are not directed at you. I know you're a CLA and already understand much of what I say below. I'm simply using your comment as a springboard to jump on my soapbox.

For those that like to use AE's, please don't take this as a personal attack; I'm referring to the AE as a programming construct and not passing judgement on anyone who uses them. Also, this is very much an opinion and is based on my own observations. My Labview experience is somewhat narrow, centering around single computer desktop applications, so there may be situations where an AE is the best solution. I don't claim to know all...

</---Disclaimer--->

Simple functional globals have a place. Any time a functional global crosses the line into an action engine I'm looking to replace it with a class. Using an AE may solve the immediate problem sooner, but it also imposes more constraints on the unknown, future modifications. You are painting yourself into a corner and the longer you stick with it the harder it is to get out.

To expand a bit on what I said about layering api's here, when you create an action engine you are creating a chunk of data with associated actions that apply only to that chunk of data. Those actions define the api your AE supports. Now suppose the AE grows to the point where you want to shift some internal behavior off to a sub vi. Like it or not, that sub vi has just become part of the public api. You cannot change that sub vi without considering how it will affect code in countless other places.

"But," you say, "I know that sub vi isn't supposed to be used anywhere but in the AE!" Easy to say now. What will you do when, in order to fill a change request, you have the choice between a quick fix by using the sub vi someplace you didn't intend 'just this once,' or a more time consuming fix by changing the behavior of the AE itself? Furthermore, when somebody else works on that code, how do you convey to them the difference between, and enforce the correct usage of, the public api versus the private api?

Every VI we write is essentially a mini api. Every action a public api exposes places constraints on how you can change that api in the future. AQ recently talked about the problems associated with publicly accessable vis in vi.lib. Those VIs are part of the public api even though they were not intended to be used by the public simply because they can be used anywhere. Trying to add functionality to the intended public api without changing the behavior of the unintended public api is extremely difficult, and sometimes impossible. Good api design involves exposing, or making available to the public, only what is necessary and no more.

Applications that don't use the classes or libraries are programmed with, in effect, one giant public api. Any vi can (and probably will) be used anywhere, which often results in a very complex vi hierarchy and interactions that are difficult to disentangle. We try to manage that complexity by organzing our projects into subfolders and using naming conventions. Unfortunately naming conventions and disk hierarchies cannot enforce the intended usage. For that we need classes and libraries.

</soapbox>

Nice spaech that I'll think about more, but unitl then let me add to this thrad by throwing out a Q.

I am the only person at my company (about 7 CLA's depending on what day it is) that has taken the plunge into LVOOP. There are four others that are familiar with OOP or LVOOP. Alomost everyone of of our applications is different! Aside from a DAQ board or two I have never (seldom, I re-use my Dew-Point Hygrometer AE in a bunch of apps going back to LV 6.1) worked with the same widget twice.

So as we kick-off new projects we turn to each other and say "we could use LVOOP on that part..." but then we look at the time limitations and say "but we don't have the time to do a LVOOP version" so we use the AE pattern.

So my management and coworkers don't want to take the chance on LVOOP because many of the pay-offs are not for us, pay-offs.

So I am looking for others to comment on how I can help my co-workers to take the plunge.

BTW:

I have started to collect some reusable classes but it just seems to take longer to to a brand new LVOOP class to support a one off interface.

WEll I was thinking while typing so let me reply that wrapping the AE's methods and putting them all in a library go a long way toward a proper API. Set public and private and it get close to what LVOOP can do.

Take care!

Ben

THe "Dictionary Challenge" was won by those who used AEs.

See here.

http://zone.ni.com/devzone/cda/tut/p/id/5305

Ben

This is somewhat of a tangent, but I have a question about the term "action engine." This term appears frequently on LAVA but I admit I haven't paid that much attention to it. In this thread the acronym "AE" appears before anyone uses the term "action engine," which is confusing enough, but what concerns me more is that I'm not sure what the term means.

In particular, I did a search on action engine with Google and didn't find anything relevant before I hit this LAVA link (Action Engine), where at least one participant equates it with a statemachine. Is this the case? If so, can we please use the term statemachine, given that it has much broader (and well-defined) usage not only with NI but also with UML and general software design? If there is a difference, can someone please clarify for the benefit of those (including myself) who might be confused?

Paul

AE= Action Engine >>> loosly a Functional Global Variable.

I wrote about them here

http://forums.ni.com/ni/board/message?board.id=170&message.id=240328#M240328

and also explain where the term came from.

Ben

Looks like we're too late: http://atwonline.com...l?storyID=18715

Even though I "knew that" it is terribly depressing hearing another inteligent person come to the same conclusion.

living up the the name "Nebulus" (what is he talking about now!)...

So the only hope for those of that fear the reprecusions is in the US court system to call into question the "commerce" clause of the contitution which if I undertstand correctly is what is being used to to give the authority to the US legislature to pass law to govern all issues where inter-state commerce is involved. The tenth ammendment has been ignored long enough. My wife will hate me for even thinking such a thought but, "I wonder how much it cost to bring an issue before the Supreme court?". Maybe if I start saving my allowance now... To think I once gave up my rights to defend what we have now. Who knows, maybe this will be enough to get some movement behind the idea of a new contitutional congress. Wait a minute! I still have reason to hold out hope.

Ben

Ahh, I missed the part about using it across a network. I have no idea if it is possible to implement a singleton across PCs as I've never done any networking code in Labview. That said, I suspect that it is possible using the proxy pattern.

...

No you didn't. I interjected that part just to highlight the power of a VI served AE.

I don't even want to spend the grey-matter on figuring out how I could do it without the AE since my brain keep interupting and saying "this would be a peice of cake with an AE."

Ben

I started a new job yesterday that I think is going to be great, and I just got my CLA results...I PASSED!!! Life is good!

Congratulations!

Do you have any notes you would like to share to help those of use who have to re-certify (next week) ?

Ben

...

An even older instance of the same joke on youTube:

OMG! Now the BBC isn't on board! I just don't know who to beleive anymore! I guess I should believe no-one

Brain always works better after the coffee kicks in. The Fearless Vampire Killers, Roman Polanski, see this link

http://en.wikipedia.org/wiki/The_Fearless_Vampire_Killers

But the main reason I brought this up was to ilustrate that if the Climate rules kick in before we KNOW, the CO2 laws will be vrtual garlic to protect us from the Global Warming Vampire.

Ben

I do not agree that most of the scientist in the IPCC are fussy in their science and the science they have as basis for their statements are not well founded. It is not that political. Well IPCC are composed of scientists, all peer-review have its flaws , it science problem in general. The fact is the US har increase it CO2 emmisions with 26% since Kyoto, therefore companies in US has not save as much energy as you would have done if US would have ratified that treaty. 12 years have been lost already. So that Climate Gate is so large in US and not in Europe is not surprising, it is threat for many industrialists. They do not think of the benefits or the alternative cost..

It is large risk if the climate would change as in IPCCs worse case scenario, the cost are very very high, enormous! The cost to do change although the decision basis might(a very low risk) be wrong is much much less.

In many European countries the adoption of the Kyoto protokoll has made us move faster against greener energy like windpower and biogas. The heavy industries have also seen the that benefits for saving energy is very large and have short pay-off time.

I believe it was an old vampire movie that featured a scene where someone pointed out the garlic to keep vampires away. Another replied "there are no vampires around here!" and the first replied "see how well it works!"

This is not just a joke in an old movie. Here in the US it is common practive and is concidered good edicate (?sp? behaviour) to say "God bless you" when someone sneezes. Strangers that would normally say nothing to you will say "God bless you." if you sneeze in public. From what i understand, that practices goes back to the dark ages when it was observed that shortly after people started sneeizing they would become ill and often act posessed afterwards. The thought at the time was that the soul left the body at the moment of a sneeze and the sound of the sneeze was the soul screaming. Since the body was temporarily devoid of a soul the person was subject to demonic possesion so say "God bless you." was a way to help prevent demonic possesion. My point is that un-founded beliefs can become part of our lives if nobody stops to question the pratice.

Human nature makes me nervous when a change in behaviour is attributed to a supposed "truth".

I can see a desperate move on the side of those that want to push forward with all of the possible implications if global warming is shown to be real. If they can get the rules set in stone soon they can point at the lack of global warming as a sign "Look how well it is working!". The last thing we should do in rush into something that has so many far reaching reprecusions.

THe move by the EPA yesterday (I question the timing) that CO2 and five other green-house gases are now recognized as being harmful to humans. Under existing US law the EPA is now obligated to regulate these gases.

Will they?

I can't say.

But if they do we COULD find out who Cass Sunstien is and his out-look on the methane producing cattle we insist on eating.

[set Kring's Law = suspended]

The fermentaion of beer produces CO2 and COULD be regulated.

[set Kring's Law = active]

THe remainder of this post was omitted because I already sound crazy enough.

Ben

... Ok, now let's see how many people try to justify murder by calling it by another name...

The bait has been smelt and rejected.

Ben

So if I'm understanding this correctly, the action engine has a giant cluster input containing fields for every piece of data that ever needs to be passed into it. And then you have a sub vi for each unique action that the AE can perform.

This sounds exactly like a class, except less flexible and more complicated. Why wouldn't you simply use a class?

That was not one of the options listed.

If you run that AE on one node you can serve it to multiple nodes using VI server Invoke Node call by reference. I would you that approach rather than a class becasue I have not figured how to implement a Singlton that will work across machines (without bending over backwards). Is is possible to implement a Singlton across PC's?

Willing to learn.

Ben

Thanks, I'll see if I can make that approach work. What about the case where my shared instrument needs to do many functions , each with several inputs, such that the functional global approach would result in a very messy connector pane? Or where I need to execute an uninterrupted sequence of commands on the shared instrument?

I will use a cluster to pass the inputs to the AE where there enough fields to cover all actions. each Action then gets a proper wrapper VI that has required inputs for all of the stuff we need for that action and then bundle before invoking the AE (learned from Jim Kring).

Re the un-interupted work....

The AE should not return until that work is done.

Ben

since we have drifted to diets, I'll share mine but first I quote my wife who said

"It ain't fair!"

I used to always have a second plate so we did not have left-overs. I switched over to one plat only and to keep myself from feeling deprived, i was allowed one bowl of ice cream with no restriction on the size of the bowl. I lost 43 pounds by sticking to this diet. See my wife's quote.

Ben

I'm building a system that can run up to 4 concurrent chemical reactions. My plan is to have 4 independent "reaction" objects that each execute in parallel, but they all need access to some shared components such as the liquid handling system that adds chemicals to each reaction, and the analysis equipment to check reaction progress. I'm looking for comments on the best way to make sure that only one reaction at a time can access the shared equipment. It seems like the traditional approach would be a semaphore, but there are all these other options available. For example, I can put all the functions for the liquid handling system into a single FGV, make it non-reentrant, and prevent overlapping access. Or I can put the automation refnum (it uses ActiveX) into a DVR or single-element queue to limit access. What is your preferred approach? What if I have 2 analysis instruments, and each reaction should use the first one that's free?

Taking this a step further (and overlapping with the recent questions about singleton classes), say I create a class to wrap the liquid handling operations. Do I wire that class to all the reactions after opening the automation reference? Is there a clean way to store that reference inside the class so that I don't need to directly wire that class everywhere it might be used?

Thanks for any comments; I already have some of this working but I can't effectively discuss my design with coworkers (I'm the only programmer on the project) so I'm looking here.

The FGV would be my first thought. I have used it to do exactly the same thing. It also scales well so when my customer said they want a PC at each production line in addition to the master machine that can serve the AE to the other machines via VI Server.

Ben

While I generally agree with you I would like to make an argument for the US post office. I realize they are not the most cost-effective. But I still find it amazing that for $0.42 I can mail a piece of paper across the country in a few days.

That being said when was the last time I had to mail a letter where I could just as easily send information electronically instead. Wonder if it's possible to just get rid of the post office for mailing paper. Could the post office be replaced with a more digitized version where people email/fax letters to send, and they can email/fax/deliver the information. Then we wouldn't need mail trucks to deliver documents from a city to another, just have the a document email from city to city, and then delivered that way. I'm sure there's alot of problems with what I said and someone has surly thought of it before me.

My Father is retired US post office. The ineficiencies drove my Father crazy so he retired at the frist oppertunity. AS I understand it that 0.42 cents sponsored by tax dollars.

Back about 1980 the US PO was offering a service where mailing could be sent electronically and printed at the local office (it ran on a PDP 11/44 and used RM03 RM02 disk drives). From what I hear from buddies still in the buisness the hardware has been upgraded and is still available. It lets them send out up to date info.

Ben

Years ago I made a living serving computers with many of my customers being hospitals. So while backups were running I'd talk to the administrators. There main use of the computer was to keep track of who was paying and who was not. They didn't really care about not getting paid because of teh Good Samaratan Law the state reimbersed them for the non-payers. My point is that required health care has been available. Yes it was only available thru the emergencies rooms. (I'll try to get back to that).

Rather than throw up a cloud of examples of where the US government (apart from the miliraty) has never done anything right, I'll focus on what the one condition under which I would go with gov't health care.

Under the current situation the American Indians are covered by a Us gov'g run health care system. On the reservation there is a saying "Don't get sick after July" (I may have the month wrong). This saying is due the the fact that after the years funds have dried up, there is nothing to pay for any supplies.

Before we even think about doing anything about health care for anyone else, I feel the US is obligated to come thru with a good system for the Indians. So why dift off to the Idians?

When the American Indians recommend the health care provided by the US gov't, then I'll concidering going along with it.

Live up to our existing obligation before we commit to more.

Ben

See this tag on LabVIEW performnace

http://forums.ni.com/ni/tagging/view_tag?tag.text=LabVIEW_Performance

and when you finish that set, chase down all of these

http://forums.ni.com/ni/tagging/tagging_detail?tag.cloud_grouping=tag&tag.cloud_style=related&tag.max_age=all&tag.message_scope=all&tag.user_scope=all&tag.tag_scope=list&tag.id=671&tag.visibility=public

When you finish all of those you'll be lecturing us on the topic.

Ben

My SO thinks Sarah Palin is "hot" (not that he would ever vote for her) so she's kinda a sore subject with me.

If it's true that there's been no mention of Climategate in any of the major news outlets, I do find it concerning. I could either think of it as a Big Leftist Tree-Hugging Conspiracy, or, what is probably even worse, blame it on the fact that global warming / climate change is becoming a boring topic that your average Joe no longer wants to talk or hear about. Unlike Sarah, who everyone wants to talk about. Because she's hot.

She can field dress a moose so of course she's hot.

Re Boring

If there were not a move about to use the Global Warming as a license to create laws based on it, it would be just another boring science story. But it is being used to argue for laws that will have far reaching impacts on everyone in the US if they pass Cap and Trade or enter into the world wide argreement. Ca-n-trade will not only put a tax on every unit of energy we are consuming now as well as establish a government agency that will determine how much everyone is allowed to produce. Since the decision of the agancy will determine who is paying what, we will be taxed dispite not haveing reporesntaion in that decision. Those who lust after power would like one of those jobs. It is also not limited to the obvious energy side of things but also can extend to the amount of CO2 produced while raising that steak dinner since it turns out our livestock produce a lot of CO2.

Ben

Can't speak for the media in general, but the Associated Press had 11 reporters "fact" checking Sarah Palin's book. Obviously Sarah Palin is more of a threat to world peace than the biggest scam in history.

I rarely watch the news on TV, but when I do it's always Fox. One day Neil Cavuto had a global warming, uh, er, I mean "climate change" "expert" and Neil called him out on it: "Why are we calling it 'climate change' now and no longer calling it global warming?" I was a little embarrassed that such a question even had to be asked.

And when 0bama singled them out a few weeks ago I figured they must be hitting very close to home. It only further validated Fox in my eyes.

We are drifting from the topic but I'm game to wonder.

I don't think there is a world wide conspirency but I would not be supporised if many people are scamming the system with the agregate effect appearing to be a conspiracy.

My opion as it stand today (subject to change when i learn more) is/are

Sara Palin is scary because she is completely unpredctable (did you see her resigning as governer coming?). Her face book update about "death Panels" set the news organization off to deal with that. Her book set new record for numbers of printings prior to release. I suspect this is due to many people lossing confidence in the leader we have and want to find someon outside the Washington belt-way to setp up. Her backing of the independant candidate in the 23 district of NY state almost helped him win (counting of absentee balots were getting him close).

I beileve it was the 17th ammendment that changed the slection of senators from an appointment by the governor of the sates to direct election. That ammendment combined with the rules of seniority in the senate means that "Mr Smith Goes to Washington" just can't happen. THe only way to get anything done in either house is to get the party in power to run with it. I still hold out hope that a new constitutional congress will be called for so that the monopoly of powers held by the two parties in the US can be broken.

There are other factors that play into what gets covered. The most imporatant being sponsor $$$s. They have to fill that screen with something that keep people watching through te commercials. One of the easiest things to present is "the talking heads" since no writters or fancy expensive graphics involved. So if the News programs want to maintain the source of cheap air-filling stuff, they don't want to piss-off the talking heads. So running off to cover a story that could upset those that keep the air filled, may be a prudent approach.

FOX on the other hand is burning up the ratings and agian I can only specualte that is for the same reason that Sarah is ggeting coverage, people are looking for someone to tell them what they can accept as being the truth, nad FOX seems to be the next best thing.

Re: FOX being singled out

I really have to give a shout-ou to the White House press crew (proper name escapes me, association of all networks that cover the White house) refused to interview X if FOX was not included.

Again thank you for the inteligent exchange.

Ben

Ben, the government impinges upon your right to own and bear arms all the time. Without all kinds of regulations, limitations, certifications, or permits, the average citizen can't own artillery, fully-automatic weapons, or even a shotgun with less than an 18" barrel.

A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed.

Your birthright only exists because at the founding of this country there was no standing military. It was the expectation that every able-bodied man would show up equipped with his own gun, ready to fight the Redcoats. Every 2nd Amendment case that has gone before the Supreme Court has ended up being interpreted within this historical context. 230 years later, we have standing armies, and furthermore we don't need to go out and hunt for our meals. One could well make an argument that the 2nd Amendment is obsolete.

Keep in mind my stance on this: I agree with you that the government should not be able to take away individual ownership of guns (unless you're a convicted felon, which is yet another digression...) But I also believe that rights and responsibilities are inseparable. Our right to keep and bear arms comes with an implicit social responsibility that this will be done in a manner which does not infringe on the next guy's rights to life, liberty, and the pursuit of happiness. And so we have laws and regulations which delineate actions for the common good. Watch what happens when I take your statement about cars and change a few words here and there:

I could shoot any type of gun I want as long as bullets never leave my own property. To shoot a gun in a public space, I need a license. Public spaces are a shared resource built and maintained by the community for our mutual benefit. The community agrees on the rules under which that shared resource is used. I can't fire a gun on the public spaces and render them dangerous for others...

I love a good debate, too. Thankfully, this is a forum with polite, educated, and articulate contributors. Ever try this stuff on, say, the Rants and Raves page on Craigslist? Some real whackos there.

Thank you!

I agree with most of what you said and I am not a student of the Supreme Court so I can't comment on their historical findings.

RE: Rights and Responsibilities

I also agree that my right end where anothers begins. One of the ushers at my wedding accidently shot and killed his brother when they found their dad's gun (he was a police officer). I am responsible for what I do with my gun and nobody else.

I also see my responsiblity extending beyond judicial use of the gun. I feel I was given a gift from my fore-fathers of the freedom that was built into the US plan. This was part of teh reason I served in the military when I was young since I was taught that it exists only because people where willing to put their lives on the line to defend it. So I raised my hand and swore an oath to defend it from all enemies both forign and domestic. A move to change the system that I swore to defend in such a way that its existiance is threatened is also my responsiblity to defend. Guns in the hands of responsible citizen willing to stand up to enemies that defend that system seems to me to be a wonderful fail-safe to safe-gaurd the system from domestic threats. This idea is not just mine or what my father taught me.

Thomas Jefferson wrote;

"When the government fears the people, there is liberty. When the people fear the government, there is tyranny."

http://www.davar.net/QUOTES/LIBERTY.HTM

From where I sit (short of a another contituional congress) I see no other way the US government will ever fear us.

Again thank you for the exchange of ideas.

Ben

...

From Physics Today dated 2 Dec 2009 "Jones Steps Down as head of climate unit"

http://blogs.physicstoday.org/politics/2009/12/jones-steps-down-at-head-of-cl.html?type=PTALERT

Ben

I'm neither a rabid right-wing gun advocate nor left-wing gun control wimp. I have no issues, however, with the prudent control and regulation of the purchase, ownership, and transfer of firearms. I do not believe these concepts abrogate or limit our constitutional right to keep and bear arms. The UN's program is entirely focused around the illegal trafficking of firearms, and their statements need to be considered within that context, not some conspiratorial they're-out-to-get-us mindset. I don't see the evil intent that others do.

Let me draw a parallel to illustrate my feelings on the subject: I don't think that owning a gun should be any easier than, say, driving a car. In order to get a driver's license, a person needs to demonstrate sufficient knowledge and proficiency to prove that they are not a danger to themselves or others. Employed correctly, an automobile or firearm can be put to constructive use in a way that benefits the owner. Incorrect use results in property damage, injury, or death. Right now, it's way easier in most states to buy any kind of gun than it is to get a driver's license, and I think that is wrong.

Let the flaming rage on...

I don't want to fight but I do enjoy a good discusion. It is importatnt that we share these thoughts.

I could drive any type of vehicle I want as long as I never leave my own property. To drive a car on a public road, I need a license. Roads are a shared resource built and maintained by the community for our mutual benefit. THe community agrees on the rules under which that sharde resource is used. I can't drive a tank on the roads and render them useless for others. Similarly I can't drive on the road with a vehicle that is not inspected. Use of the public road ways is a privledge that is accesable via a license as per the public agreement.

The right to own and bear arms can not be impinged apon. This is right that I received as result of being born a US citizen and has been mine ever since. To place restriction on my access to acquiring guns is in effect determining if I have one that I can bear. I feel that is was no accident that this was ammendment #2 right after the right to free speech. The founding fathers set up the FEDERAL government (not national, the states agreed to associate) in such a way as to limit it powers (the tenth ammendment is currently being threatened). I am glad they explicitly spelled out hte right to own guns.

Thank you for reading and I welcome your thoughts.

Ben

never mind

(I get so emotional, baby.)

That image illustrates what the recent G20 in Pittsburgh looked like from a residents point of view.

Ben

...

------------------------

There's a lot more I found that I haven't posted simply because of time constraints. The measures promoted may not (or may, I don't really know) be intended to be a global ban on guns, but they clearly provide an easy avenue of attack for anti-gun proponents to pursue their agenda. I see the NRA's activities in this matter as a proactive defense.

And yet another nice post! Thank you.

In the event anyone was wondering I am one of those "that cling to God and guns..." (Obama 2008 compaign rally) residents of Westrn PA who lives within walking distance of the place where the Whiskey Rebelion started. Speaking only for myself, I view my gun as my last line of defence against an out of control government. Judging by conversations with friends, I am not alone.

Ben

[insert your favorite pro-gun bumper sticker slogan here]

My favorite is "When guns are outlawed only outlaws will have guns."

This is a tricky one.

Ben's suggestion is OK, but has a little problem, the value will change after a mouse leave event.

What you can do is add a notification and a user event. Every value change you sent the new value to the notification.

In a second loop you read out the notification with this little construct inside a secondary loop (text only no LabVIEW at this PC:

-Wait 25 ms

-Get Notification, time-out 0 ms

-Check time-out status

-TimeOut == true

-You had no new 'value change' events in the last 25 ms and you can trigger a user event to act on the actual value change

Loop again.

This makes sure that you only get a user event for that control when the value changing is dead for 25 ms, most of the time fast enough.

Ton

It only chages if I mouse down while in. (I will try to attach example).

Ben

Guage.vi