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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 know what drivers are used under the hood, but I've recently used G-Audio to interface to the mic/speakers for a LabVIEW application I was working on.

My problem was on a windows machine but I managed to solve it; I found that using LVCompare also segfaulted on the same file, but did not segfault with the -nofp command line option. With this I was able to confirm the specific file that both LVMerge and LVCompare were segfaulting on, and systematically delete half the code and re-test whether LVCompare would crash. After a few hours I was able to track down the offending piece of code to a random chart; I'm honestly still not sure what was causing them to segfault, but deleting and replacing the chart fixed the issue. Hope this helps someone else out there!

I would suggest rabbitmq, i want(ed) to present it at a LabVIEW user group (LUGE) but haven't done it yet. It's very powerful. I use redis and did a quick presentation (in french) at LUGE recently, i haven't used the stream feature though, I only used it as cache.

Hi My advice for managing multiple versions of LabVIEW is always the same : >>> Install only one LabVIEW version per partition if you also need to install any driver, toolkit or module. Or need other software that integrates with LabVIEW in some way. No exceptions. I do have VMWare installed with Windows XP to be able to open ancient LabVIEW versions like 6.1 or read the old CHM help files, accepting the sluggish performance of the VM environment. I avoid using it for anything 'serious'. To manage the span between LabVIEW 2018 and 2024 I would divide the disk into two partitions and install two copies of Windows and then install LabVIEW. To manage multiple partitions and selecting which to boot from by default, I recommend installing EasyBCD. But you don't have to. Windows creates a simple multiboot menu itself. There are other options too. But they require some dedication going into the art of multiboot management. ¤ You can install Windows on an external USB3 connected disk, SSD or FlashDisk. Microsoft abandoned the concept in 2020. But a program called Rufus revived the concept and now there are many tools that gives this as an opportunity. Works splendidly even with Windows 11. ¤ Some laptops ( and desktops of course ) support easy change of the disk. Sometimes using a replaceable disk craddle instead of the DVD drive. Good luck

Redis is certainly high performance and suited to multiple, loose writers, readers and subscribers, with bindings for so many ecosystems. One of its several features, which I haven't perused, are Streams. I'd be curious too to know whether continuous cross-app data streaming could be efficiently implemented using them.

I think this is fixed now. Please check.

When you send the message you encapsulate the message as a cluster of string and variant. You don't seem to unwrap the variant from the name/variant cluster in the receiver. What I expect to see is something like this in the receiver:

Aren't DVR's just LabVIEW's take on pointers?

Had the same issue. Removing a VI from a lvlib, using Pane Relief to set splitter size and moving it back to the the lvlib worked for me to. Thanks!

yeah that is the payload 😉

That's how I'd do it. Then combine that with the Foreign Key Sort from my Array package, putting the Time Stamps into the Keys, then paths into the Arrays, and it will sort the paths from oldest to newest. Reverse the array and index at 0, or use Delete From Array to get the last element, which would be the newest file.

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

Indeed. It's not a full solution as it doesn't support multiple streams, audio or other encoding types. But if you want to get the audio then you need to add the decoding case (parse is the nomenclature used here) for the audio packets in the read payload case structure.

To be honest, I always thought those should be in the Visible Items menu.

To analyze large time series remotely I have a client application that splits the data transfer using two methods; It will break down the periods into subperiods that is then assembled into the full period by the receiver *and* if the subperiods are too large as well they are retrieved gradually (interlaced) by transferring decimated sets with a decimation offset. So, as a result of this I need to merge multiple overlapping fragments of time series (X and Y array sets). My base solution for this just concatinates two sets, sorts the result based on the time (X values) and finally removes duplicate samples (XY pairs) from it. This is simple to do with OpenG array VIs (sort 1D and remove duplicates VIs) or the improved VIM-versions from @hooovahh, but this is not optimal. My first optimized version runs through the two XY sets in a for-loop instead, a for loop that picks consecutive unique values from either of the two sets until there are no such entries left. This solution is typically 12-15 times faster than the base case (<10 ms to merge two sets into one set with 250 000 samples on my computer e.g.). Has anyone else made or seen a solution for this before? It is not as generic as the array operations covered by the OpenG array library e.g., but it still seems like something many people might need to do here and there...(I had VIs in my collection to stitch consecutive time series together with some overlap, but not any that handles interlacing as well). It would be interesting to see how optimized and/or generalized it could be solved. I have attached the two mentioned examples here , they are not thorougly tested yet, but just as a reference (VIMs included just in case...). Below is a picture of the front panel showing an example of the result they produce with two given XY sets (in this case overlapping samples do not share the same value, but this is done just to illustrate what Y value it has picked when boths sets have entries for the same X (time) value): Merging XY series LV2022.zip

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

I confirmed the behaviour on my machine. It is that the Write doesn't pass the file reference through if there is an error in. Seems like a bug to me.

I did a quick test in a private MediaWiki instance and got it to work using the fix available on GitHub: Switch jquery.cookie to mediawiki.cookie by paladox · Pull Request #1 · debtcompliance/TreeAndMenu · GitHub

There is a list of discord servers on the wiki: https://labviewwiki.org/wiki/LabVIEW_Community_Managed_Discord_Servers

There is a "best practices" document (this too) but I suspect you are looking for a less abstract set of guidelines.

@Ravi Beniwal, I have the same problem, VIPM reports that missing dependency for me too. If it isn't required could it be removed ? If it is required could it be included ? I suspect it is included in version 1.7.028 which does not report the error. I spent(wasted !) time looking for the dependency and downloading it, only to realise it might not be needed as it launches OK from the LV IDE menu Tools\LabVIEW Task Maanger.... Peter

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

You can add text labels to a dial. It does not turn it into an enum but sort of works like you would expect (change the data type to U8).

I don't have good examples to share, but here are a few helpful links for you: NI has an article dedicated to DVRs, which also explains the fundamental idea: http://www.ni.com/product-documentation/9386/en/ Here is a short video that explains how to use a DVR and some of the pitfalls: https://www.youtube.com/watch?v=VIWzjnkqz1Q Of course, you'll find lots of topics related to DVRs on this forum.

Which is funny because when I took them, I thought the CLD was much harder than the CLA.

I used scripting and low-level VI editing to generate a VI with every single decoration object in LabVIEW, at least those with ID's 0 to -4096. There may be some out of that range (and many in that range don't have a valid image associated with them) but this range contains a lot of them. 0 to -4096.vi