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So a couple of years ago I was reading about the ZLIB documentation on compression and how it works. It was an interesting blog post going into how it works, and what compression algorithms like zip really do. This is using the LZ77 and Huffman Tables. It was very education and I thought it might be fun to try to write some of it in G. The deflate function in ZLIB is very well understood from an external code call and so the only real ever so slight place that it made sense in my head was to use it on LabVIEW RT. The wonderful OpenG Zip package has support for Linux RT in version 4.2.0b1 as posted here. For now this is the version I will be sticking with because of the RT support. Still I went on my little journey trying to make my own in pure LabVIEW to see what I could do. My first attempt failed immensely and I did not have the knowledge, to understand what was wrong, or how to debug it. As a test of AI progression I decided to dig up this old code and start asking AI about what I could do to improve my code, and to finally have it working properly. Well over the holiday break Google Gemini delivered. It was very helpful for the first 90% or so. It was great having a dialog with back and forth asking about edge cases, and how things are handled. It gave examples and knew what the next steps were. Admittedly it is a somewhat academic problem, and so maybe that's why the AI did so well. And I did still reference some of the other content online. The last 10% were a bit of a pain. The AI hallucinated several times giving wrong information, or analyzed my byte streams incorrectly. But this did help me understand it even more since I had to debug it. So attached is my first go at it in 2022 Q3. It requires some packages from VIPM.IO. Image Manipulation, for making some debug tree drawings which is actually disabled at the moment. And the new version of my Array package 3.1.3.23. So how is performance? Well I only have the deflate function, and it only is on the dynamic table, which only gets called if there is some amount of data around 1K and larger. I tested it with random stuff with lots of repetition and my 700k string took about 100ms to process while the OpenG method took about 2ms. Compression was similar but OpenG was about 5% smaller too. It was a lot of fun, I learned a lot, and will probably apply things I learned, but realistically I will stick with the OpenG for real work. If there are improvements to make, the largest time sink is in detecting the patterns. It is a 32k sliding window and I'm unsure of what techniques can be used to make it faster. ZLIB G Compression.zip

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"

It is not that LabVIEW MAY unregister the reference, but that it WILL unregister the reference as soon as the top level VI in whose hierarchy the reference was created goes idle. This is by design and the only way to prevent that is to either keep that hierarchy active until any other user of that refnum has finished or delegate creating of the refnum to the place where it is needed, for instance through a LV2 style global maintaining the reference in a shift register and when being called for the first time it will create the refnum if the shift register contains an invalid refnum. True Actor Framework design kind of mandates that all refnums are created in the context of where they are used not some other global instance that may or may not keep running for the time some Actor is using the refnum.

Hi everyone, Just want to share our open source project "Labview Python Bridge". Connect labview apps with python apps in realtime with multi-processing data queues. https://github.com/jmor2000/labview_python_bridge If anyone has any questions or suggestions for new developments / features, let me know. Cheers Jeff

Are you seriously expecting anyone to install a random executable on their system from an unknown publisher, provided by an anonymous person on the web, where one can't even get a proper link in Google to the actual company page? Sorry, but anyone doing that should not be allowed near 5m of a computer system!

Absolutely echo what Shaun says. Nobody banned them. But most who tried to use them have after some more or less short time run from them, with many hairs ripped out of their head, a few nervous tics from to much caffeine consume and swearing to never try them again. The idea is not really bad and if you are willing to suffer through it you can make pretty impressive things with them, but the execution of that idea is anything but ideal and feels in many places like a half thought out idea that was eventually abandoned when it was kind of working but before it was a really easily usable feature.

Seems like this one has "escaped everyone's grasp" too. ParallelLoop.ShowAllSchedules=True Because was only checked from the password-protected diagram of ParallelForLoopDialog.vi (LabVIEW 20xx\resource\dialog). Present since LabVIEW 2010. When activated, allows to apply more advanced iteration partitioning schedule. In other words, instead of this you will get this Сould this be useful? I can't say. Maybe in some very specific use-cases. In my quick tests I didn't manage to get increase in any productivity. It's easy to mess up with those options and make things worse, than by default. Also can be changed by this scripting counterpart.

Look at this new download on VIPM https://www.vipm.io/package/bjm_lib_request_power/

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.

参考 https://www.vipm.io/publisher/opengds/ OpenGDS UML Editor by OpenGDS

Available in the new ECL version 4.6.0

@Rolf Kalbermatter my team and I still use in some systems here! In fact this very last week we have needed to add some lua stuff to an old project.

There should be a forum on the dark side for that, but anyway, here you go. LabGRAD_21.zip

For fun. 😄 "Science isn't about why; it's about why not!" - Cave Johnson

Found it here @Ajayvignesh https://github.com/sandialabs/LVTM

Reentrant execution may be a safe option. Have to check the function. The zlib library is generally written in a way that should be multithreading safe. Of course that does NOT apply to accessing for instance the same ZIP or UNZIP stream with two different function calls at the same time. The underlaying streams (mapping to the according refnums in the VI library) are not protected with mutexes or anything. That's an extra overhead that costs time to do even when it would be not necessary. But for the Inflate and Deflate functions it would be almost certainly safe to do. I'm not a fan of making libraries all over reentrant since in older versions they were not debuggable at all and there are still limitations even now. Also reentrant execution is NOT a panacea that solves everything. It can speed up certain operations if used properly but it comes with significant overhead for memory and extra management work so in many cases it improves nothing but can have even negative effects. Because of that I never enable reentrant execution in VIs by default, only after I'm positively convinced that it improves things. For the other ZLIB functions operating on refnums I will for sure not enable it. It should work fine if you make sure that a refnum is never accessed from two different places at the same time but that is active user restraint that they must do. Simply leaving the functions non-reentrant is the only safe option without having to write a 50 page document explaining what you should never do, and which 99% of the users never will read anyways. 😁 And yes LabVIEW 8.6 has no Separated Compiled code. And 2009 neither.

I haven't had much time to investigate this until this month, but I think I've found the cause. XNodes on the production computer were not designed optimally. In the AdaptToInputs ability I was unconditionally passing a GenerateCode reply, thinking that the AdaptToInputs is only called when interacting with the XNode (connecting/disconnecting wires). It turned out that LabVIEW also calls the AdaptToInputs ability once, when the VIs are loaded and any single change is made, no matter if it touches the XNode or not. As I had many such non-optimal XNodes in many places, it was causing code regeneration in all of them. Besides of that some of my VIs had very high code complexity (11 to 13), because of a bunch of nested structures. When the XNodes regeneration was occurring simultaneously with the VIs recompilation, it was taking that a minute or so. After I added extra conditions into my AdaptToInputs ability (issue a GenerateCode reply only, when the Term Types are changed), the edits in my VIs started to take 1.5 seconds. Still the hierarchy saves can be slow, when some 'heavy' VIs are changed, but it's a task for me to refactor those VIs, so their complexity could decrease to 10 or less. By the way, my example from the previous page was not suitable for demonstrating the situation, as its code complexity is low and the Match Regular Expression XNode does not issue a GenerateCode reply in the AdaptToInputs.

@hwkim418 There are many ways you can go about this. Here's a few examples using JSONtext. (VI saved in LV 2019) object_deserialization.vi

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

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.

Hello ladies and gentlemen! Prepare yourselves for a massive wall of text. Thank you in advance. First time poster, long time lurker. Over the last decade I have found answers to a myriad of Labview related questions I've had on these forums, and I'm hoping some of you can help me out with my current conundrum. I've a solo developer for a large labview based automation project. I have worked with other labview developers in the past, but we've always kept what we were working on very compartmentalized because nobody ever wanted to deal with LVMerge. At the time they all said Labview effectively had zero way to merge VIs. Since those old days (9 years ago) we've come a long way. Unfortunately like many engineers I am horrible about UI/UX design - I'm trying to fix basic functionality, I don't care that you can't find the button (at least I don't care right then). But because of how solid the software is getting we're finally in a good position to start dedicating time and effort into improving our UI flow and design. So in the run up to this, and knowing I had basically zero experience with LVMerge/Compare except that the previous developers considered it "impossible", I did a few tests. My goal was to continue some development in the block diagram of the main top level VI in my own git branch, while another developer worked on UX changes on a second git branch. Then when he was ready we'd merge everything back together. All of his changes were focused on the Front Panel - he never opened the block diagram once. He was moving things, resizing things, changing captions and boolean texts, but never labels, and then adding various decorations as he wanted for clarity and organization. My initial test merges worked flawlessly. I was surprised how easy my small merges worked. From there he tinkered away when he could over 4ish weeks on the UI and I kept my usual pace on the main top level working on various bugs. I tried to limit what I was doing in the top level - most of the block diagram changes I made were cosmetic. It needed some TLC. Anyway fast forward and now we're ready to merge everything back together and ... I can't. I cannot get it to work. I've tried so much stuff. At first the errors were almost always during the LVCompare phase, usually about an insane block diagram object on the "base" vi. I'm familiar with heap peak so after a crash I'd comb the error log as well as I could (wish that thing had some documentation) and then try to find the offending object and fix it. More often then not I wouldn't see an issue with the object at all, and lots of the advice online is "just delete and remake the object" but I hate that solution because it means I fundamentally don't understand the actual problem, and when I'm merging three different versions of a big VI that gets tough to do. I've been experimenting with the tools, and eventually turned off auto resolve. Okay cool that would get me through the compare stage and actually open LVMerge where I could select which versions of things I wanted. From here it became a game of cat and mouse where I go through changes one by one till I get a crash, investigate, fix, change something related to said crash, and then run it again. This has been time (and sanity) consuming. It never worked, and eventually I got stuck on a merge change that I couldn't even identify what it was changing between the three, but I know that no matter which I select it crashes. I've kept trying various things since then. Resizing the tab control positions to be exactly the same Deleting a few FP objects on the base and FP update versions that I had removed when making BP changes on my version Adding a few objects I created for the same reason Added all 3 versions of the VI to the main most up to date project, opening and running them all to make sure there are no serious insane objects that are breaking them. They all run. This is by no means an exhaustive list of everything I've tried, but its what comes to mind right now as the major tries. Currently the state I'm in is that when I run it with all 3 versions with all the changes from above made to them, I can't get through the Compare stage because it crashes with a insane object error about "undo.cpp" which makes zero sense to me. What is it undoing? I tried limiting the number of Undos in LV settings, that didnt help, I tried increasing the limit greatly, that also didn't work (maybe didn't increase enough? Trying that now). I'm really deep in the weeds on this one now, and I would love some fresh perspectives. What's probably going to happen is that I'm going to write it all off as a lesson, and we'll just have the UI dev make his changes again on my current most up to date version - but I would really love to figure out the compare and merge process, and best practices for using it. The documentation for these is abysmal. There's basically nothing. I could probably pay for NI's annual subscription and maybe get some direct help from them but I had it out pretty big with some NI sales guys a few years ago when they transitioned away from perpetual licenses to the subscription model, and I don't want to pay them on principle; but I will if needed. Ultimately even if we do the changes again, I'd still like some best practices on where we went wrong and how to avoid this in the future. We're growing fast, and I could see having another full time labview developer working with me in the future and would love to come away from this with as many answers as possible on how to work in a team on labview binary files. If you've made it this far all I can say is thank you. Now please send help. PS: some info I should of added we use Labview 2021. I don't think we're on SP1, I don't remember why not, and I am willing to try updating. also willing to pay the sub and just upgrade to 2025, but not without good reason like someone tells me all about how they solved so many issues with Compare/Merge in the last 4 years and its going to be so much better I'm attaching my most recent error log from the crash I had last night. Its a doozy, reporting a TON of objects on both the FP and BP as insane. lvlog2025-08-11-15-32-09.txt

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 am also rocking version 4.2.0b1-1 for the same reasons.

QUIC

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.

This topic is repetitive. Please go here “Sequence Toolkit“ ”

I think this is fixed now. Please check.

Yup. There is: MMAP (1.0.1).

I cannot look at your file, but I suggest save the data to TDMS or any binary format of your choice. Once the file is saved, then you can convert it to text.

Technically it is a resource collector, but not exactly in the same way typical garbage collectors work. Normal garbage collectors work in a way where the runtime system somehow tracks variables usage at runtime by monitoring when they get out of runtime scope and then attempts to deallocate any variable that is not a value type in terms of the stack space or scope space it consumes. The LabVIEW resource collector works in a slightly different way in that whenever a refnum gets created, it is registered together with the current top level VI in the call chain and a destroy callback with a refnum resource manager. When a top level VI stops executing, both by being aborted or simply executing its last diagram element, it informs the refnum resource manager that it goes idle, and that will then make the refnum resource manager scan its registered refnums to see if any is associated with that top level VI and if so, call its destroy callback. So while it is technically not a garbage collector in the exact same way as what Java or .Net does, it still is for most practical purposes a garbage collector. The difference is, that a refnum can be passed to other execution hierarchies through globals and similar and as such might still be used elsewhere, so technically isn't really garbage yet. There are three main solutions for this: 1) Don't create the refnum in an unrelated VI hierarchy to be passed to another hierarchy for use 2) If you do create it in one VI hierarchy for use in another, keep the initial hierarchy non-idle (running) until you do not need that refnum anymore anywhere. 3) If the refnum is a resource that can be named (eg. Queues, Notifiers) obtain a seperate refnum to the named resource in each hierarchy. The underlying object will stay alive for as long as at least one refnum is still valid. Each obtained refnum is an independent reference to the object and destroying one (implicit or explicit) won't destroy any of the other refnums.

I'm excited to release ViPER ViPER is an Object Oriented design Framework that supports dependency injection and recursive object creation. Systems are assembled at runtime from a collection of pre-built components defined by an Object Definition Document. Please visit the project on GitHub https://github.com/kurtafriday/ViPER I've presented this framework at several GLA Conferences, for an overview and guidance please view. GLA 2021 https://labviewwiki.org/wiki/GLA_Summit_2021/Open_Source_ViPER GLA 2020 https://labviewwiki.org/wiki/GLA_Summit_2020/ViPER_-_A_LabVIEW_Dependency_Injection_Framework This branch of ViPER has been used by us to develop systems in regulated industries for several years, it's solid and reliable, however its windows only. I'm working on ViPER_WinRT which is compatible with Windows and RT and we have already used it for several systems. I'll be releasing ViPER_WinRT in the coming months. I'll work to get ViPER onto the VIPM Tools Network soon. I'm looking forward to the feedback and I hope you enjoy and get value from this framework. Ping me if you have any questions. kurt@medulla.net

We use the MPSSE.dll LABview driver from Benoit. We are trying the i2c read 1 byte and multi bytes. We expect ack for all bytes except the last byte with nak. During read, we understand that the I2C master drives the ack/nak. However, ack and nak happens randomly. Any body have any suggestions Thank you Dan

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).

Well that's okay I felt like doing some improvements on the image manipulation code. Attached is an improved version that supports ico and tif files and allows to select an image from within the file. For ico files it basically grabs the one image you select (with Image Index) and make an array of bytes that is a ico file with only that image in it, and then displays it in the picture box. For Tif files there is a .Net method for selecting the image which for some reason doesn't work on ico files. Edit: Updated to work with Tifs as well. Image Manipulation With Ico and Tif.zip

Looks like someone beat me to it! Oh well, I already exported it (also for 2009, incidentally) so I'll post it here in case it'd be more convenient to use a regular VI file. 0 to -4096.vi

I think I have this fixed. Tried a compiled version of the transport library; this worked without issue. I made the timeout changes, which did not seem to have an impact on performance. I then recompiled everything (the server-side code is used in multiple applications on the system); the delay I was seeing with the one message/response went to expected amounts in tests. I've been waiting to test this with the whole system up and going; unfortunately, we've been battling drive issues that are stopping everything else. Can't definitively say it's fixed. Can't point to a smoking gun. I'm appreciating this forum and the people on it right now.

Hi all, sorry i had to do some other work. @ O_o: We already took a look into the UML editor from GOOP: The code is horrible. @drjdpowell: Thank you for your Picture and your inspiration. Up to now we try an other way. We will report if we found a solution. Thanks again Oliver

Mwuhahahahaha! Three config tokens have escaped your grasp! I modified them specifically for folks like Flarn! They don't appear as plain text anywhere in the EXE (or in any VI for that matter). Do they guard any great secret of LabVIEW? I'm not telling! But you can have fun pouring through the code and looking for interesting bits and trying to figure out what you need to put in your config file. LabVIEW 2013 or later. Good luck.

Hi All, I'm looking for a good resource that explains LabVIEW's Execution System / Thread Allocation / Thread Priority system. As a background to the reason for my request: I have an application with over 50 parallel loops running at fixed but configurable times. Twenty of these loops are calling a .net Dll and are thus not in a Timed Loop (there is a known issue according to NI support with calling a .net dll in a timed loop where the call time is large ie. upwards of a second). The remaining loops are performing other data acquisition. Each loop is what I call a Task Controller - it looks after a specific piece of hardware, taking requests for data (via queues), performing data acquisition and then pumping the result back to the requester. In order to seperate the timing of the functionality (and allow multiple requesters access to the same data), this process is not sequential but occurs in parallel loops. So there is a lot of parallel activity going on. I notice that as more of these loops fire up, the slower the remaining loops are. The CPU usage tends to stay around 7-8% during this time irrespective of how many loops are executing. Note that the .net dll calls (up to 20) are reasonably slow calls and each could take up to 6 seconds to execute. The .net dll has been written to handle multi-threading. The PC is a hyper-threaded quad core (ie 8 logical cores) @ 3.3GHz. Kinda a meaty machine. I should also mention that the majority of the VIs are re-entrant. The only non-rentrant VIs are some FGVs and a few User Interface VIs that reference the data in these FGVs. And before you ask the FGVs are simply Get/Set for a handful of cluster points. So I figure it's a simple case of thread starvation. Every VI is currently set to the Standard Execution System (via Same as Caller) with Normal Priority. I figure that adjusting these settings on the top level Task Controller vis may assist in spreading the load to the remaining available, but not executing, threads. The SubVIs under each Task Controller will continue to use the Same As Caller setting, allowing me to seperate logically each Task into appropriate Execution Systems. Any thoughts?

The configuration is contained in the *.ini file for the built application along with other properties such as vi server configuration. Here's an example of the content that updates the Other1 and Other2 execution systems maximum thread count for each priority. You can generate this programmatically as part of the application build spec with a Post-Built Action : ESys.other1.Normal = 20 ESys.other1.High = 20 ESys.other1.VHigh = 20 ESys.other1.TCritical = 20 ESys.other2.Normal = 20 ESys.other2.High = 20 ESys.other2.VHigh = 20 ESys.other2.TCritical = 20 Note that you could also just use the same property settings in your LabVIEW.ini file for the same effect in the development environment. I believe this is all threadconfig.vi actually does however it doesn't touch any application build specs (not that sophisticated I'm afraid). Here is a quick post build vi I cobbled together to generate the entries on every application build:

The OpenG Pipe Project does just that. It is a LabVIEW Library that replaces the System Exec function and returns pipe refnums for the three standard IO interfaces and functions to read and write to those refnums. The project hasn't been released yet as I consider it not entirely release quality but it does work for me and I have actually used in in several of my projects already. Since there is no officially released package yet you can't just download it through VIPM from internet. But here is a copy of a package you can install using VIPM. oglib_pipe-1.0-1.ogp

The candles are starting to flicker to life... I read that and immediately wondered why the first case causes a broken run arrow and the second doesn't. (Hey, it was in CAPS... it was easy to skip the preceeding sentences.) Then the word "object" in the PRTC context help hit me over the head. From my end user perspective, previous versions of Labview don't make a distinction between classes and objects. (For example, the To More Specific Class prim has 'Target Class' as an input that in reality accepts an object.) Despite my attempts to differentiate between the two when posting, in my head I often use the terms interchangably. I'll have to work hard to change my way of thinking. I'd give you more kudos if I could...