ShaunR

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Had a chance to look more closely now. You can save yourself having to load "special" VIs that take a custom event via controls or detecting mouse over/move events on the child FP (checking mouse coordinates in region etc in the main VI) by attaching a callback to the VI when you load it. The callback can be attached to any VI to piggy-back the child VIs events and inject your own user event that you can access in your main VI. You can attach these call backs to not only the VI server events (close, mousemove, resize et. al.), but controls/indicators as well. I think it would greatly simplify you main VI.

That was the best presentation I have seen for a number of years on any subject

If you use the OS tab control via activex or .NET. you can add/remove pages dynamically.

I wouldn't say "many", probably just two - the "string" anality and you can't wire an object to it. The former is trivial to resolve and based on a whim. If it did not behave in this fashion, it would be great for 99% of cases. The latter? (1%) I expect extremely difficult and was probably flagged as "too much hassle", but it would have had far reaching positive implications for networked transfers and possibly dynamic instantiation of objects.

Naah. It's just splitting the frames into separate VIs. There is no real practical difference between a class and an AE apart from code bloat In fact, many people put classes into polymorphic VIs so they can get back to a single VI (ala an AE ) once they've split out all the functions. If it's warranted, I usually just cut out the middle-man and create the polymorphic VI with a LV2global which solves the many conpane connection problem and gives adapt-to-type as well as a nice selector instead of an enum (and avoiding some of the nasty side effects of adding items to enums). Slightly off-topic. But I've noticed a preference of combo-boxes as selectors instead of enums in LV2013.

Just looked now. There are only two frames. Exit and "No Event", Default. Well. I'm going to shift/clarify my position, just slightly, although I maintain all I have said is correct. The QSM is as described and the other example is a QMH, but the QMH example doesn't define a QMH, but it a more common one. As I said on another thread. A QMH just means it's a buffered message handler (buffered by a queue, shift register, lemons). How it is handled or how it is buffered is irrelevant. It is a genericism that has buffered messages and are handled by some code. So the QSM is a QMH with specific characteristics that make it behave as a state machine and I have tried to define what those differences are in comparison to a non state machine QMH.

Indeed. In the sense of an ordered list of messages and "how" it is realised (queue primitive or while loop with shift register) is, IMO, irrelevant (thanks for spelling out MHL->Message Handling Loop. Maybe I can make up the acronym OLOM Lets see if it catches on ) A message handler, handles messages. Period. A queued message handler buffers the messages before it handles them. That's really all there is to it.

OK. Here's how I see it, for my sins (it's rather similar to FGV and AE). A queued message handler is a collection of frames that are basically an API of discrete functions driven by an ordered list of incoming messages. There are no inter dependencies between the frames and they can be called in any order at any time. You are sort of right in your thinking out loud, in that they generally do not have shift registers but that isn't a defining feature since it may have shift registers to maintain the state of that individual function/frame (lets say a counter). But that state is not used by any other frames and is not propagated. The module, as a whole, does not have any state. Any frame, at any time can be executed without regard to previous calls or calls to other frames. An example of this definition would be something like a Drive controller. It has moveTo, Stop, Reset, getPosition etc. The "state" of the drive would be maintained by an external module (usually a sequence engine) which would call the methods in the right order and at the right times. The drive state is maintained external to the module - it is just a collection of functions. There are very good reasons for doing this, most notably, that the sequence engine knows of other dependent states of the system so you don't do something like drive a ream into the bed when no part is present. Externalising the state in this case helps you decrease application specific functionality of the module and reduce module interdependence. A QSM is also a collection of frames driven by an ordered list, but they are interdependent and must be called in various orders depending of the internal state of the module. Additioanlly, the frames may add messages that were not on the original list. As said before. I use the reading of file as a trivial example as I've seen it many times and think "what a lot of code to achieve very little" There, you may have open, read, write and close frames, but the API interface is ReadFile/WriteFile. When actioned, each frame is called in the correct order dictated by the internal decisions about the state of the file. It is no longer just a collection of functions, it has interdependent frames and maintains internal state (of the file whilst executing).

Well. There is no real difference between FGV and AE from your definition apart from an arbitrary break point to try and make a differentiation.. They both have methods. They both enforce interaction to the internal memory only via those methods and they both only operate on the data supplied externally to their terminals. It's a bit like saying there is a special name for a class that only has methods and no properties-it's still a class. What about a self incrementing counter that gives you the next value when it is called? That only has a Get method-what is that under your definition? If you really wanted to make a differentiation so as to define a FGV as something different from an AE,, Then you could argue that a FGV does not contain state (only functions and its output is predictable and constant given the inputs), whereas an action engine does contain state and it's output is dependent on the internal state. Under this definition, the Get/Set would be a FGV and the self incrementing counter would be an AE. But I think the number of methods is a bit weak

Agreed. I don't think there is a difference apart from terminology. The get/set FGV is just a problematic corner case AE. I equate AEs with singleton classes rather than global variables and that a LV2Global is the protected storage of an AE just as the private cluster is in a class.

I didn't attend. But I watched the vid. The QMH was confusing to me. I don't see any difference personally between an actor "Do" and QMH as I don't think there is one and it seemed that you were not really convinced there was one either I do however see a huge difference between Actors,QMH and Queued State Machines (and you mentioned the JKI QSM as in reference to QMHs) and in that context I agree with many of the things you often espouse. The usual example I give for QSMs is reading a file, since it is a lot of code and a lot of messages all to do something that can be done in a single simple VI and there is little benefit in splitting out the states. That VI would then be put in a QMH or Actor. In terms of presentation skills. The only thought I had was something I was taught which is that it's not productive to read verbatim what is on the slides. The audience will do that. It only eats time and doesn't purvey any more information. ........later.... Nope. I do know the difference between a QMH and Actor and I don't think it's semantics. QMHs don't contain state and the state is driven by the producer. If they do maintain state, then they are QSMs (QSMs and Actors being subsets of QMHs). So an Actor can be the same as a QSM if it does not manage it's state (unusual) but a comparison between Actors and QSMs would have been clearer.

Pretty much my response when I found out it behaved like this. Indeed. Although I don't think the decision has anything to do with speed, That comes from the fact it is compiled rather than labview code. It's just an unnecessary literal interpretation of "string" that hobbles the API. You see this kind of thing quite often when designed purely from spec without use cases. There is no advantages to this behaviour apart from specmanship, but there are serious disadvantages IMHO The frustrating thing for me (as I think I said to AQ when he was talking about his serializer) is that it is probably the one feature in LV2013 that would make me consider switching from LV2009, They've fixed a few of other things I wasn't happy with 2010 onwards that made me completely resistive to upgrading and the JSON Vis were just the sort of feature upgrade I have been waiting for all these years. So as excited as I was to see these in the palettes, I think I will stay with 2009 and use the 3rd party libraries as it is a lot cleaner, more compact and vastly safer.

Very pleased to see the New JSON Encode and Decode in the palettes of LabVIEW 2013. I've looked at using them instead of the various libraries out there and I'm in two minds whether I will convert my current apps or use them in the future instead of those 3rd party libraries now I have had a chance to play.. Let's start off by saying they work great They are orders of magnitude faster than 3rd party ones and they adhere vehemently to the JSON standard. It's the last bit I'm in two minds about. JSON is subset of Javascript (EMACS). Javascript is dynamically typed, which means that any variable can hold any type and although a string may have quotes around it, it does not preclude inserting it into, or operating on as a numeric type. Whilst the JSON spec does specify that string types be encased in quotes, Javascript (and PHP, for that matter) programmers don't really care and it doesn't break their code if they are present or not. Therefore it is very common to see quotes around numerics and even quotes left off of strings and most parsers will cope with this. LabVIEW is strictly typed and when the JSON Decode encounters quotes, it will error if you have defined the field as, say, a double. and then will not process any further fields. This is a right, royal pain! It also misses a trick that would make our lives so much easier and our code much simpler. Take, for example, the following real JSON stream from MTGox. { "channel":"dbf1dee9-4f2e-4a08-8cb7-748919a71b21", "channel_name":"trade.BTC", "op":"private", "origin":"broadcast", "private":"trade", "trade":{ "type":"trade", "date":1376196221, "amount":0.3333, "price":102.95507, "tid":"1376196221462784" ,"amount_int":"33330000", "price_int":"10295507", "item":"BTC", "price_currency":"USD", "trade_type":"ask", "primary":"Y", "properties":"limit" }} The "price_int"," amount_int" are encased in quotes when quite clearly they are integers and, more importantly, we need to manipulate them as integers. This forces the use of cluster elements that are strings and then to convert those fields to the appropriate type. It is compounded further since the structure is nested which means we have to unbundle all of the elements and then re-bundle to our desired types as we cannot use a single cluster definition. Additionally, the "date" is a numeric of the correct type, but that is not very useful in this scenario since it will need to be converted to a string. So defining that field in the decoding cluster as a string would have been a bonus. . This is the conversion using the native JSON decode.vi. This is using the JSON API available in the CR. The JSON API in the CR is much more forgiving in that the cluster, alone, decides on the type. So type conversion can be done transparently by defining the cluster regardless if a value is quoted or not. This yields a much simple, easier to maintain VI and, should the server generating the JSON decide to strictly adhere to removing quotes from integers; it will not break our code as it would with the native VIs. The native JSON decode has a "strict validation" boolean that states It would be useful if this boolean also disabled type checking of quoted strings. It would also be useful if it didn't stop at the first field it couldn't interpret and tried harder to continue. I could live without the latter, but not sure I can without the former - hence my ambivalence. Did I mention how fast the native VIs are?

New - Event Inspector Window (you're gonna love this!) - Never had a need for this, but it may come in handy if you don't know what events you are firing . New - High Priority events - Don't have a use case at the moment. But I can see edge cases where it may be useful. New - Flush Event Queue Function - I've always considered flooding event queues as bad and lazy programming, so I think this will just let bad and lazy programmers off the hook. New - VI Scripting methods and properties for events - Good for tool-chain developers. But no real use case for me. Improvements to the Edit Events Dialog: - Didn't notice Will look again You forget the big one - MOUSE WHEEL . By far the most useful, just a shame it's the only one.

There's a setting in the labview options under environment that should sort that out (it puts cleanupVisa=True in the ini file).

Another method is just to create a windows task (equivalent of chron-job). Apart from just scheduling you can also launch on specific OS events.

I've often wondered why you can't program directly from the hierarchy window in LabVIEW. The hierarchy window is one of, if not the, most under-developed feature of LabVIEW IMO.

Seeing as your link button isn't working I didn't see the Pipes anywhere on there. But I did find a build of lvzip for x64 which everyone has been asking for Did you really create that a year ago?

I'll have a quart of what you are drinking

Don't know about LabPython but the intermediary DLL source for the openG zip and pipe libs definitely isn't distributed with the packages as I would have recompiled them for x64 by now ;P Are they elsewhere? Link perhaps?

As opposed to a dynamic library that you cannot use on other platforms, you mean (e.g.LV x64),. I don't mind this approach as long as people distribute the C source for the intermediary, which seems to never happen

ooooh.Gonna have to check these out. • Flatten To JSON • Unflatten From JSON

Let John find all the issues then switch when you start a new project (if it is after SP1). By all means "play" but as far as real projects are concerned; you are spot on with your current regime IMHO It's all very well "embracing change" but changing/upgrading tool chains is a huge project risk and there have to be specific, justifiable benefits. Unfortunately, I have not seen any practical benefits of note after LV 2009 for my projects. Lets see if that changes with LV 2013.

It's been a long time since I was at school (where we covered this sort of stuff) but I think you are asking about torque and angular momentum.