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A customer asked me to create a powerpoint explaining the advantages of LabVIEW. While putting together the practical rationales, just for grins I asked Chatgpt to create a presentation explaining the philosophy of LabVIEW in a Zen sort of way. Here is what it came up with. Zen_of_LabVIEW.pdf

I spent a long time online with YouTube support and finally got to the bottom of it. The Channel is back, and all the links work!

Phew that is a pretty strong opinion! Although I personally am not a fan of the overall style of DQMH none of my problems are with the scripting/wizards or placeholder text. I think any framework that tries to do "a lot" will be complicated... your own personal framework (which you likely find trivial to use) is likely to be a bit weird to others. DQMH is extremely popular for a reason... To paraphrase the words of a wiser person than I, "please don't yuck someone elses yum"

Many years ago I made a demo for myself on how to drag and drop clones of a graph. I wanted to show a transparent picture of the new graph window as soon as the drag started, to give the user immediate feedback of what the drag does and the window to be placed exactly where it is wanted. I think I found inspiration for that on ni.com or here back then, but now I cannot find my old demo, nor the examples that inspired me back then. Now I have an application where I want to spawn trends of a tag if you drag the tag out of listbox and I had to remake the code...(see video below). At first I tried to use mouse events to position the window, but I was unable to get a smooth movement that way. I searched the web for similar solutions and found one that used the Input device API to read mouse positions to move a window without a title and that seemed to be much smoother. The first demo I made for myself is attached here (run the demo and drag from the list...). It lacks a way to cancel the drag though; Once you start the drag you have a clone no matter what. dragtrends.mp4 Has anyone else made a similar feature? Perhaps where cancelling is handled too, and/or with a more generic design / framework? Drag window out of listbox - Saved in LV2018.zip

The examples you provide are invalid JSON, which makes it difficult to understand what you are actually trying to do. In your VI, the input data is a 2D array of string but the JSON output is completely different. Your first step should be to define the types you need to produce the expected JSON output. Afterwards you can map your input data to the output data and simply convert it to JSON. The structure of the inner-most object in your JSON appears to be the following: { "Type":"ABC", "IP":"192.168.0.0", "Port":111, "Still":1, "Register":"Register", "Address":12345, "SizeLength":1, "FET":2, "Size":"big", "Conversion":"small" } In LabVIEW, this can be represented by a cluster: When you convert this cluster to JSON, you'll get the output above. Now, the next level of your structure is a bit strange but can be solved in a similar manner. I assume that "1", "2", and "3" are instances of the object above: { "1": {}, "2": {}, "3": {} } So essentially, this is a cluster containing clusters: The approach for the next level is practically the same: { "TCP": {} } And finally, there can be multiple instances of that, which, again, works the same: { "EQ1": {}, "EQ2": {} } This is the final form as far as I can tell. Now you can use either JSONtext or LabVIEW's built-in Flatten To JSON function to convert it to JSON {"EQ1":{"TCP":{"1":{"Type":"ABC","IP":"192.168.0.0","Port":111,"Still":1,"Register":"Register","Address":12345,"SizeLength":1,"FET":2,"Size":"big","Conversion":"small"},"2":{"Type":"ABC","IP":"192.168.0.0","Port":111,"Still":1,"Register":"Register","Address":12345,"SizeLength":1,"FET":2,"Size":"big","Conversion":"small"},"3":{"Type":"ABC","IP":"192.168.0.0","Port":111,"Still":1,"Register":"Register","Address":12345,"SizeLength":1,"FET":2,"Size":"big","Conversion":"small"}}},"EQ2":{"TCP":{"1":{"Type":"ABC","IP":"192.168.0.0","Port":111,"Still":1,"Register":"Register","Address":12345,"SizeLength":1,"FET":2,"Size":"big","Conversion":"small"},"2":{"Type":"ABC","IP":"192.168.0.0","Port":111,"Still":1,"Register":"Register","Address":12345,"SizeLength":1,"FET":2,"Size":"big","Conversion":"small"},"3":{"Type":"ABC","IP":"192.168.0.0","Port":111,"Still":1,"Register":"Register","Address":12345,"SizeLength":1,"FET":2,"Size":"big","Conversion":"small"}}}} The mapping of your input data should be straight forward.

In a previous life, I used to teach a CLD level class using this book, and enjoyed it a lot -- Some of it is certainly outdated at this point, but I think it still has a lot of solid info / strategies in it. I've attached the files as a .zip file to this post. Good luck! Effective LabVIEW Programming Files.zip

I have put some effort into improving the VI icons in Messenger Library, in hopes of making things clearer. I have particularly been trying to get rid of the magnifying glass icon, which was standing in for too many concepts. I have also tried to improve the Palettes by putting the standard VIs (that one would most commonly use) in the root-level palette: The 2.0 version also introduces Malleable API methods (the orange-coloured ones), which make code cleaner. If anyone could spare some time, it would help me to have feedback. Especially from people who have not used Messenger Library before, so I can get an idea if the key concepts come across. New 2.1.3 version is available here: https://forums.ni.com/t5/JDP-Science-Tools/New-icons-for-Messenger-Library/m-p/4412550#M192

You want an ability to override the Equality or Comparison operators? I'm unsure, whether it really existed in OpenG packages, but now you have those neat malleable VIs, that let you do that: Search Unsorted 1D Array , Sort 1D Array , Search Sorted 1D Array. They have an additional input to specify your own equals or less function in a form of a custom comparison class or a VI refnum. There's an article to help: Creating a Custom Sorting Function in LabVIEW

This is exactly what was said in that ancient thread: Tree control in labview. So if you add 65536*N to the Item Symbols property of the Listbox and have the "Enable Indentation" option activated, you shift the symbol/glyph and the text N levels to the right. Could be useful for simple 'parent-child' relationships, if you don't want to use a Tree. And still it's used in Find Examples / NI Example Finder window:

I once went for an interview where they gave me a coding test and asked me to modify it. It was a very long time ago so I don't remember the exact modification they wanted (nothing to do with memory leaks) but I do remember the obtain queue and read queue inside a while loop with the release queue outside. I asked if they wanted me to also fix the memory leak as well as the modifications and they were a little puzzled until I explained what you have just said. I must have seen (and fixed) this while-loop bug-pattern a thousand times since then in various code bases. I also created this VI which I generally use instead of the primitives as it intialises on first call, can be called from anywhere, and prevents most foot-shooting by rolling them all into a single VI and ensuring all references but 1 are closed after use. Queue.vi

Those aren't typo's and errors. They are tests to see if we are paying attention.

In the past I have used the IMAQ drivers for getting the image, which on its own does not require any additional runtime license. It is one of those lesser known secrets that acquiring and saving the image is free, but any of the useful tools have a development, and deployment license associated with it. I've also had mild success with leveraging VLC. Here is the library I used in the past, and here is another one I haven't used but looks promising. With these you can have a live stream of a camera as long as VLC can talk to it, and then pretty easily save snapshots. EDIT: The NI software for getting images through IMAQ for free is called "NI Vision Common Resources". This LAVA thread is where I first learned about it.

Just to share how I got around this: By deleting 1 front panel item at a time I found that one single control was causing PaneRelief to crash; an XY graph. Setting it temporarily to not scale and replacing it with a standard XY graph (the one I had had some colours set to transparent etc) was enough to avoid having PaneRelief crash LabVIEW, but it would now just present a timeout error: I found a way arund this too though: the VI in question was member of a DQMH lvlib that probably added a lot of complexity for PaneRelief. With a copy saved as a non-member it worked: I could replace the graph, edit the splitters with PaneRelief without the timeout error (even setting the size to 0), then copy back the original graph replacing the temporary one, and finally move the copy back into the lvlib and swap it with the original. Voila! What a Relief... 😉 I probably have to repeat this whole ordeal if I ever need to readjust the splitters in that VI with PaneRelief though 😮

I confirm that this license is nearly identical to the standard EULA we use for our commercial products. Some wording is not applicable to a distributed palette of VIs like this. Our intention was to share a few reusable tools, used internally, with the community. Ideally, we should have released them under a standard open-source license such as MIT or a similar option. These VIs have been released “as-is,” without support or any guarantee that they will function for your specific use case. You may need to troubleshoot or fix any issues on your own. Feel free to use them in any context. I’ll look into whether it's possible to update the packages on the tool network to replace the current license with a more standard open-source one.

I put a temporary ban on inserting external links in posts (except from a safe list). We'll see what affect it has.

This is the modern 2020's equivalent of "works for me".

Your reporting of spam is helpful. And just like you are doing one report per user is enough since I ban the user and all their posts are deleted. If spam gets too frequent I notify Michael and he tweaks dials behind the scene to try to help. This might be by looking at and temporarily banning new accounts from IP blocks, countries, or banning key words in posts. He also will upgrade the forum's platform tools occasionally and it gets better at detecting and rejecting spam.

Apparently they moved it under Visible Items Edit: This also affects other types of structures.

Well, there are two aspects. The first is the technical one from hackers diving into the software and unhiding things that NI felt were not ready for prime time, to complicated for simple users, or possibly also to powerful. The main reason definitely always is however: if we release that, we have to spend a lot more effort to make it a finished feature (a feature for internal use where you can tell your users: "sorry that was not meant to be used in the way you just tried") is maybe 10 - 20% of development time than the finished feature for public use. There is also support required. That costs money in terms of substantial extra development, end user quality documentation (a simple notepad file doesn't cut it), maintenance and fixing things if something does not match the documented behaviour. And yes I'm aware they don't always fix bugs immediately (or ever) but the premise is, that releasing a feature causes a lot of additional costs and obligations, if you want to or not. The other aspect is, if someone who is an active partner and has active contacts with various people at NI, he is infinitely more likely to be able to influence decisions at NI than the greatest hacker doing his thing in his attic and never talking with anyone from NI. In that sense it is very likely that Jim having talked with a few people at NI has done a lot more to make NI release this feature eventually, than 20 hackers throwing every single "secret" about this feature on the street. In that sense the term "forcing NI's hands" is maybe a bit inaccurate. He didn't force them, but led them to see the light! Not out of pure selfless love, but to be able to officially use that feature for himself. The according Right-Click framework was a proof of concept to see how this feature can be used and mainly an example to other users how it can be used, and indeed once it worked it had fulfilled its purpose. That it was not maintained afterwards is not specifically JKI's fault. It is open source, so anyone could have picked up the baton, if they felt it was so valuable for them. The problem with many libraries is actually, if they are not open source and free, many complain about that, if it is open source and/or free, they still expect full support for it! In that sense I have seen a nice little remark recently:

Well, you are missing some important details in "The story of how this came about". So maybe indeed "it is worth a post of its own". It was LabVIEW 7.0 where they forgot to put a password on one of the VIs shipped with LabVIEW. And that VI had some node(s) on its block diagram including, I think, the BD reference property for the VI class. The community indeed got excited. But what did NI do? They tried to hide everything again in LabVIEW 7.1! I made a joke then that "our mother" NI must had had a PMS so she put the most interesting toys on a top shelf. So I made a"ladder" for us, kids, to get to them again and called it hviewlabs was me then, because that was a name of my company I used to sell my LabHSM Toolkit, an actor framework with actors controlled by hierarchical state machines (statecharts), long before the Statechart toolkit by NI, "THE Actor Framework", DQMH, and even before LVOOP. After PJM_Labview has published his private class generator http://forums.lavag.org/index.php?showtopic=307&hl=# and class hierarchies http://forums.lavag.org/index.php?showtopic=2161# and http://forums.lavag.org/index.php?showtopic=314&hl=hierarchy# (neither topic is available anymore) it became clear how to get access to private classes, properties and methods. However, it wasn't convenient enough. My PMS Assistant made it really easy. It gave back the access to those features to a much wider community of LabVIEW enthusiasts As you can see from the PMS topic discussion, by that time brian175 already had made his DataAct Class Browser. And he got really excited about the possibility not only browse but also to actually create objects, property and method nodes with the properties and method NI didn't want the users to see. By April of the same 2006 he figured out object creation too and incorporated the capabilities of PMS Assistant into DataAct Class Browser. At that point, I guess, NI decided that "the cat is out of the bag" and there is no point to resist. Nevertheless even after VI Scripting was made released by NI some classes, and even some properties and methods of public classes remain hidden even in LabVIEW 2024. I wonder why DataAct Class Browser is no longer available (as of January 2025) as well as original findings by PJM_Labview even here, on LavaG. Did NI "politely asked" admins to remove all that and just forgot about my PMS Assistant?

Unfortunately, many of those are bots. I've disable user:pages long time ago, because of the spam. If there's anyone that deserves a lot of credit lately it's @LogMAN. He's doing amazing work cleaning up the pages and adding/editing content. There's a push recently from NI to support the Wiki and promote its use to the broader community and within NI internally as well. So, we should see more traffic and more activity than usual, which is great. This is one of the reasons for the recent stability updates. I encourage everyone here on LAVA to find whatever LabVIEW topic they are passionate about and start adding some pages or even fleshing out some existing content that needs improvement. One way to start would be to find some information that you always wish NI had easily available on their website but could never get easy access to. Then create that on the Wiki.

I don't do Discord. I don't even do Ni.com. Feedback isn't really necessary. I only knocked it up because I went down a rabbit hole and wasn't impressed with the existing LabVIEW solutions. I thought I'd throw it in here to see if someone could improve it. My solution is optimised but there may have been a better alternative solution or maybe someone had a nice JPEG one (LSB doesn't survive JPEG compression). You might get a mention in the readme just for responding

You may also want tell people where you can actually download or at least buy this. Although if you want to sell it, do not expect to many reactions. It is already hard to get people to use such toolkits when you offer them for free download.

QUIC

If the child classes are statically linked in the code (via class constants, or whatever other mechanism you use), then this approach should always work, because the child classes will always be in memory.

I kind of liked this idea and wished VIM's could allow for such a backpropagation. Even had a thought of making an idea on the dark forums. But then I played a while with the Variant To Data node. It doesn't play well. It can't determine a sink, if a polymorphic VI is connected or even when a LV native (yellow) node is connected. Borders of structures are another issue, obviously. So, it'd require making two ideas at least: to implement VIM backpropagation and to enhance the Variant To Data node. (As a hack one could eliminate the Variant to Data in their code with coerceFromVariant=TRUE token, but then the diagram starts to look odd and no error handling is performed). If someone still wants the code, shown in the very first post, it's here: https://code.google.com/archive/p/party-licht-steuerung/source/default/source?page=3 (\trunk\PLS-Code\PLS Main.vi). And these are the papers to progress through the lessons: LabVIEW Intermediate I Successful Development Practices Course Manual. Nothing interesting there for an experienced LV'er though. XNodes demonstrated here work a way better, and could be a good alternative (if you're OK with unsupported features, of course). As I tried to adapt them for my own purposes, I decided to improve the sink search technique. It surprised me a bit, that there's still no complete code to walk through all the nested structures to determine a source/sink by its wire. Maybe I didn't search well but all I found was this popup plugin: Find Wire Source.llb. It stops on Case structures though. I have reversed its logic to search for a sink instead of a source and tried to apply recursion, when it encounters a Case structure. Well, it's still not ideal, but now it works in most my cases. There are some cases, when it cannot find a sink, e.g. wire branches with void terms: Too many scenarios to process them all. Nevertheless, this little VI might be useful for someone. You may use it as a popup plugin, of course, or may pull out that Execute Find Wire Destination (R).vi and use it in your XNodes. As an example: Find Wire Destination.llb Already tried such nodes in a work project. I must admit that not all the time back-propagation is suitable, so about 50/50. But when it's used, it works.

In addition to the LV native method, there are options with .NET and command prompt: Get Recently Modified Files.

The popular serializer/deserializer problem. The serializer is never really the hard part (it can be laborious if you have to handle many data types but it's doable) but the deserializer gets almost always tricky. Every serious programmer gets into this problem at some point, and many spend countless hours to write the perfect serializer/deserializer library, only to abandon their own creation after a few attempts to shoehorn it into other applications. 🙂

I'm prone to use JKI state machines for this sort of simple test sequencing. It is easy to learn, and surprisingly powerful once you become proficient with it. You can also use JKI State Machine Objects (traditional JKI SM wrapped in a class) which makes it simple to support multiple parallel state machines, and which also supports using events. Regards, Rick

Open the search function (Ctrl+F) and browse for the "NaN" constant. A dialog pops up telling you this palette item is not supported by the Find Dialog... You can search for the "NaN" string and it will find all the NaN constants (plus all the occurrences of the "NaN" string). You can search for all other constants (pi, machine epsilon, +/-Inf, etc.), but not for the NaN constant, which is just a numeric constant with NaN typed in it. You can search for ALL numeric constants, but not for a specific one, say "1". Of course, you can search for all "1" strings in your code, and the constant 1 will show up among the search results, but it will be hidden in a long list of irrelevant results. And try to search for a constant with units... You can't. What would be nice is to look for a constant irrespective of its unit, as for instance 60 s = 1 min. Did I encode that time constant as 60 s or 1 min? I need to search for 60 AND 1 to find out.

I actually had a similar experience when first moving everything to the new OpenG structure. It broke heaps of stuff (even inside its own OpenG stuff), so I rolled back the change. Some time later I tried again, and think I did have to deal with a bit of pain initially with relinking or maybe some missing stuff, but since then things have been stable.

Close should be inside the loop. Before you start a new file you would close the old one. The file reference you get from opening the file would be put onto a shift register so that you can access it in the next iteration of the while loop. Can you share your code?

If you look at the actual array sizes, things will make a lot more sense. 1. The Build Array will add the number of expanded elements to the first dimension. The array size after the first Build Array is (2,0), which is still an empty array. 2. The Transpose Array will swap the array sizes. The array size after the Transpose Array is (0,2), which is still an empty array. 3. Again, the Build Array will add the number of expanded elements to the first dimension. In this case, it will add 1 to the first dimension, resulting in the array size being (1,2), which is no longer an empty array.

IIRC there are a couple of RTSP libs for around (a while ago now). Some are based on using the VLC DLL's and I even saw one that was pure LabVIEW. Might be worth having a look at them for "inspiration".

What doesn't work with the function: AJ_NETSDK_IPC_PTZControl() on page 21/22? Or are you not using the SDK functions to retrieve the RTSP stream but some other ready made interface for LabVIEW? Meaning you have no idea how to interface to a DLL? A few points to consider: 1) The camera may not like a secondary connection, either through the SDK or through generic TCP/IP while it is busy streaming image data to the VLC or whatever interface. 2) Trying to reverse engineer the TCP/IP binary stream protocol is likely going to be cumbersome and difficult to realize as it is usually proprietary. The SDK interface is simple enough to use, except if you lack any and all understanding about C programming. It's not a CIN node either that you will need to configure but a CLN (Call Library Node). CINs are not only legacy technology but on most modern LabVIEW versions simply not supported anymore. An interesting problem, but none I can help you as I do not have that hardware, and I would expect it to be a bit cumbersome considering above 2 points.

Started playing with XNodes a bit and noticed the same behaviour as well. Really upsetting. But there is the solution. Just send FailTransaction reply in a Cancel case in the OnDoubleClick ability of your XNode and that 'dirty dot' never appears! That's exactly what the Timed Loop XNode does internally. Looking at this description I get the impression that this reply was invented precisely to overcome that bug (was even given its own CAR #571353). Similar thread for cross-reference: LabVIEW Bug Report: Error Ring Edit + Cancel modifies the owning VI

Makes sense. It just goes to show how ingrained workflows are and little things can trip you up. I was right-clicking over the N, over the I. Right clicking 2 pixels down/up from the edge. Top edge, bottom edge, left right.

Probably not the feedback you are expecting but we really should do something about the nasty root loop API calls in the input API. I have somewhat progressed with this over the years and have the windows stuff all working for mouse and keyboard (and a little of the Linux) but I don't have a Mac so can't do anything on that. If there is some interest then let me know and I will see if I can allocate time to getting an API together.

C:\Program Files\National Instruments\LabVIEW 20xx\resource\PropertyPages\Pages\Format & Precision\pp_SetControlF&PString.vi Valid if no error.

This is by no means a full EtherCAT tutorial but, rather, introductory notes. Please, feel free to add to this post, expend and/or correct any mistakes and information.

Setting up the project:

Yes this has been done before. I believe BlueVariantView is what you are looking for. It creates a recursive tree of any data type: JSONtext on the other hand illustrates how to turn your data back into a data type.

I will change the terminal name to "Format empty input as null" to prevent reading it as referring to JSON Strings in the input rather than the entire LabVIEW string. And I'l try and give a better description:

Welcome to the LAVA! Wire your struct to a Property Node to access public properties and fields. You can set it to either read or write a value. Please be careful when changing signatures. LabVIEW does not automatically detect when the type of an argument changes. You'll have to manually update all calling sites to match the new signature which can lead to bad behavior. That said, calling by ref or by value both work. Here is a complete example for both of them: namespace DemoLib { public struct MyStruct { public string Message { get; set; } public int Number { get; set; } } public class MyClass { public string GetMessage(MyStruct data) { return data.Message; } public int GetNumber(MyStruct data) { return data.Number; } public string CreateMessageByRef(ref MyStruct data) { data.Message = "Hello from CreateMessageByRef"; return data.Message; } public int CreateNumberByRef(ref MyStruct data) { data.Number = 42; return data.Number; } } } Example.vi

You are probably getting a permissions error on the Open (windows doesn't ordinarily allow writing "c:") which will yield a null refnum and an err 8 on the open. Your err 5000 becomes a noop as does the write. You're then clearing that error so when you come to close the null refnum it complains it's an invalid parameter - equivalent to the following. Is it expected behaviour? Yes. Should it report a different error code? Maybe.

I can confirm that LabVIEW 2018 SP1 f4 (32-bit) automatically selects LabVIEW Runtime 2018 SP1 f5 when "automatically select recommended installers" is checked and LabVIEW Runtime 2018 SP1 f5 is installed. Though, it does not ask for the installer source. There used to be SFX installers that were extracted to "C:\National Instruments Downloads". When such an installer was used, the destination folder must not be deleted as it is used as a source location when creating installers in LabVIEW. Perhaps you installed the runtime engine through an old SFX installer and deleted those files at some point?

Regarding Levenshtein: Wladimir Levenshtein developed 1995 an algorithm for this. It is called the Levenshtein Distance. Some years ago I developed a VI to calculate the Levenshtein Distance. Here it is (LabVIEW 2016). Can you post your VIs in LV2020 or 2019, please. Levenshtein Distance.vi

When do we get vector graphics in LV?

I am glad that didn't ve time to install NXG 😀

Hopefully this alleviates any concerns about LabVIEW becoming unsupported in the future in favor of NXG.