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Showing content with the highest reputation since 09/22/2025 in all areas

  1. 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
    5 points
  2. We're back again this year. Free 24 hours of virtual LabVIEW presentations. Come join us! https://www.glasummit.org/ We're also looking for presenters. I know some of you all have a lot of opinions...
    3 points
  3. 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!
    3 points
  4. Hi all - sharing an open-source LabVIEW client we’ve been developing at Nominal. The idea is simple: keep LabVIEW doing what it does well on the test stand, while streaming the resulting data to Nominal for analysis, visualization, and collaboration. Instead of test data living on individual machines or desktop TDMS files, engineers can stream data directly from LabVIEW into a shared workspace, where it can be time-aligned with logs, video, and other data for analysis. Nominal's LabVIEW client supports real-time streaming, TDMS upload, and NI Linux RT. Install via VIPM LabVIEW client source on GitHub We're also building Instro, an open-source Python library for instrument control and test automation. For anyone running a mixed LabVIEW/Python test environment, we'd especially love feedback on where you draw that boundary today and what instruments you'd like to see supported. Instro source on GitHub Would love feedback from the LAVA community - on either project.
    2 points
  5. This is the nine year-old link I've saved for this - Solved: Re: New VI - default window size - NI Community It behaves oddly in that if you change it and close it before saving, it won't prompt you to save. Anyone understand this?
    2 points
  6. The recovery loop forcing is most likely related to the installation of DAQmx and other NI driver software that make under the hood use of NI-PAL and friends which is really part of the NI-PXI driver software stack. This driver goes fairly deep into the Windows PCI hardware driver stack and newer Windows versions tend to enable the newest features in the PCI chipsets. Some of these features did not even exist in the standard when DAQmx and NI-PAL that come with the standard install of LabVIEW 2020 were released. So if you want to install an older version of LabVIEW on a recent hardware, it is actually best to choose a custom install and disable installation of all hardware drivers and then install the latest version of the drivers you actually need that are still compatible with your LabVIEW version. That's of course cumbersome and the long term solution is indeed to move to a newer LabVIEW version altogether. But be aware that this problem will keep occurring. The times where hardware improvements were automatically always fully backwards compatible are definitely over. The PCI standard got so complicated over the years, and covers much more than just the traditional PCI slots that are almost unseen in modern computers. Pretty much every modern bus from USB3 and higher to Thunderbolt, all kinds of memory interfaces, and many more is nowadays using PCI technologies in one way or the other. Improving that without causing potential backwards compatibility problems got an almost impossible task. And each of the software component manufacturers from hardware firmware, to BIOS and chipset firmware to Windows drivers and vendor drivers such as NI-PAL would need to test their thing with everything else to be sure it still works. Which of course is impossible, so you end up with these issues. For LabVIEW itself I managed to install and use LabVIEW 2009 on Windows 11 without any real problems. I'm convinced that even LabVIEW 7.1 would be possible, although that most likely would require some careful hand holding and sweet talking to the installer to convince it to go fully through with it. And it might show some visual artefacts when running it under Windows 11. Hardware drivers on the other hand are a different story. The NI drivers go fairly deep into the system to allow high performance data acquisition and similar things and that has a big potential to run into compatibility trouble on newer hardware than what was available at the release date of the driver.
    2 points
  7. Hi there ! If this subject interest you, I'm currently working on a new State Machine Toolkit for LabVIEW. You can find some shorts videos about it here : https://www.youtube.com/@EmmanuelGeveaux Or some posts about it here : https://www.linkedin.com/posts/emmanuel-geveaux-93836130a_labview-statemachines-ugcPost-746286803261... This toolkit will be Open-Source, free for students, education purpose and within LabVIEW Community Edition use. I'd be happy to ear any feedback on those videos and posts. Best regards Emmanuel
    2 points
  8. This year I went to NI Connect (the new NI Week) for the first time in 7 years. I thought I would be the exception and see all those that have gone year after year. But it turns out that many of us this was our first year back, or some last year was their first year back since COVID. In general I think this is a good sign, that things are moving in the right direction. NI has some new leadership that has a LabVIEW focus, and at least at the moment appear to want to push adoption. Reversing the subscription only is a welcome change, but for many it hurt the inertia of business. Once a ship starts moving in the wrong direction it takes a while to come back. Or put another way, respect is lost in buckets and gained in drops. Plenty of businesses have likely moved away from LabVIEW and NI because of poor decisions, that in my opinion, were so NI would look more valuable for an Emerson sale. I'm in the Detroit area, and plan to retire doing LabVIEW. At the moment I think I can do that. Not long ago I didn't think that would be the case. We were just blindly paying the SSP each year. The subscription only model, made management here reevaluated things. We took a few years off. Then perpetual licenses came back again so we renewed. I think we will likely get a new perpetual license every 4 years or so. This will hurt NI since this means less users on the newest release finding issues. Building back trust will take time here, and this will likely play out in a similar way around the world for other companies.
    2 points
  9. 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.
    2 points
  10. 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
    2 points
  11. 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.
    2 points
  12. 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.
    2 points
  13. Look at this new download on VIPM https://www.vipm.io/package/bjm_lib_request_power/
    2 points
  14. 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
    2 points
  15. 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:
    2 points
  16. Going a bit off topic (ironically), but wading through those endless topic-shifting conversations on Discord feels like a step backwards....It is a nice tool for a public chat, but it makes things harder to find and follow 😞
    1 point
  17. 2026 Q3 was released the other day by the way...
    1 point
  18. 2022 Q3 is still the large majority of our projects. Windows 11 support 64 bit RT, and things work fairly well. Yes like others have said some compile cache issues but very happy. We are migrating to 2025 Q1 as needed. I haven't used it as much as I have 2022 Q3, but it seems fairly good so far. I have seen a compile cache issue in 2025 Q1, and I have seen an RT related crash with XNet in development where the build was stable. So not all the confidence in the world but fine.
    1 point
  19. You should contact the developer. It may use features not available in earlier versions and it is a source control nightmare maintaining subtly difference versions.
    1 point
  20. I'll caveat this with this is only my opinion as a European. Market forces may be completely different to my perception in the US. When I first started, LabVIEW was basically a loss-leader to sell hardware. The sales people would give it away free (or heavily discounted) if you bought the hardware. It proliferated and people like myself learnt and expanded our capabilities. Over time it launched a small consultancy industry specialising in LabVIEW. There were a few major successes such as JKI and some partnerships along with single developer consultants. The test and measurement industry had few rivals to LabVIEW's capabilities. Fast forward to today and I think the emphasis is now firmly on large organisations with enormous hardware requirements-in particular governmental organisations. CERN is an obvious one in Europe (CERN being intergovernmental) but I believe there are many in the US. The Test and Measurement was, for the most part, lost to Python and although there are one or two consultants still operating in my neck of the woods, that part of the industry is basically gone here. So. In my view there is still an appreciable number of opportunities working for large companies' in the US and Europe but if you are looking to be a self employed contractor (in Europe) then you would be better off with something else.
    1 point
  21. 参考 https://www.vipm.io/publisher/opengds/ OpenGDS UML Editor by OpenGDS
    1 point
  22. My part of the world! Unfortunately, I don't have any connections to the realm you are talking about. But I would look at Northern Kentucky University (just across the Ohio river) as they have a good CS program (or at least used to). There is also Miami University (not to be confused with the one in Florida), Wright State University (where I got my MSE), and University of Dayton about an hour north of here in the Dayton area. University of Kentucky is about 2 hours south (Lexington, Kentucky), which is about the same distance from Ohio University (Athens) or THE Ohio State University (Columbus).
    1 point
  23. I tried hard to ignore your poisonous whisperings but eventually succumbed to it. 🤫
    1 point
  24. @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.
    1 point
  25. You can 'renew' your LabVIEW CE license this way if you haven't tried it: Go to https://www.ni.com Hover over your user icon in the upper right and select "My Account". Scroll down to "Products and Services" and select "View my products". Scroll down to find your LabVIEW Community Edition and select "Renew" from the drop-down menu to the right. Apologies if you've already tried this and still had issues. Maybe someone else will find it useful.
    1 point
  26. 1 point
  27. Found it here @Ajayvignesh https://github.com/sandialabs/LVTM
    1 point
  28. A Timestamp is a 128 bit fixed point number. It consists of a 64-bit signed integer representing the seconds since January 1, 1904 GMT and a 64-bit unsigned integer representing the fractional seconds. As such it has a range of something like +- 3*10^11 years relative to 1904. That's about +-300 billion years, about 20 times the lifetime of our universe and long after our universe will have either died or collapsed. And the resolution is about 1/2*10^19 seconds, that's a fraction of an attosecond. However LabVIEW only uses the most significant 32-bit of the fractional part so it is "only" able to have a theoretical resolution of some 1/2*10^10 seconds or 200 picoseconds. Practically the Windows clock has a theoretical resolution of 100ns. That doesn't mean that you can get incremental values that increase with 100ns however. It's how the timebase is calculated but there can be bigger increments than 100ns between two subsequent readings (and no increment). A double floating point number has an exponent of 11 bits and 52 fractional bits. This means it can represent about 2^53 seconds or some 285 million years before its resolution gets higher than one second. Scale down accordingly to 285 000 years for 1 ms resolution and still 285 years for 1us resolution.
    1 point
  29. So in LV>=20, using OpenSerializer.Base64 and G-Image. That simple. Linux just does not have IMAQ. Well, who said that the result should be an IMAQ image?
    1 point
  30. 😅 You might be waiting a while, I'm mostly interested in compression, not decompression. That being said in the post I made, there is a VI called Process Huffman Tree and Process Data - Inflate Test under the Sandbox folder. I found it on the NI forums at some point and thought it was neat but I wasn't ready to use it yet. It isn't complete obviously but does the walking through of bits of the tree, to bytes. EDIT: Here is the post on NI's forums I found it on.
    1 point
  31. There is an example shipped with LabVIEW called "Image Compression with DCT". If one added the colour-space conversion, quantization and changed the order of encoding (entropy encoding) and Huffman RLE you'd have a JPG [En/De]coder. That'd work on all platforms Not volunteering; just saying
    1 point
  32. You could also check https://github.com/ISISSynchGroup/mjpeg-reader which provides a .Net solution (not tried). So, who volunteers for something working on linux?
    1 point
  33. From what I can remember, for LV 5.0.x and older RTE (i.e., a loader plus small subset of resources) was included into the EXE automatically during the build process. For LV 5.1.x there was a choice: to include RTE into the build or to use an external RTE. And since LV 6.0 only an external RTE was supposed. I could say more, such a trick is still possible for all modern versions on all three platforms (Win, Mac, Linux). The latest version I tested it on, was LV 2018, but I'm pretty sure, the technique hasn't changed much. I can't remember, from which version NI started to use Visual Studio 2015, but since then each EXE requires The Universal CRT, that is contained in Microsoft Visual C++ 2015 Redistributable. One could install such a distro on a clean machine or copy all these files from the machine, where such a CRT is already installed. Now besides of those the application will also require this minimal subset of folders/files (true for LV 2018 64-bit): On Linux it goes much easier (true for LV 2014 64-bit): For LV 2018 64-bit with a "dark" RTE it also wants And for Mac OS you can embed RTE into the application with this script: Standalone LabVIEW-built Mac Application with Post-Build Action. Of course (and I'm sure everyone understands that), the technique described above, is applicable to very simple 'a la calculator' apps and not very to not at all for more or less complex projects. The more functions are called, the more dependencies you get. If something from MKL is used, you need lvanlys.dll and LV##0000_BLASLAPACK.dll, if VISA is used, you need visa32.dll, NiViAsrl.dll and maybe others, and so on and so forth.
    1 point
  34. The thing I loved about the original LabVIEW was that it was not namespaced or partitioned. You could run an executable and share variables without having to use things like memory maps. I used to to have a toolbox of executables (DVM, Power Supplies, oscilloscopes, logging etc. ) and each test system was just launching the appropriate executable[s] at the appropriate times. It was like OOP composition for an entire test system but with executable modules. Additionally, crashes were unheard of. In the 1990's I think I had 1 insane object in 18 months and didn't know what a GPF fault was until I started looking at other languages. We could run out of memory if we weren't careful though (remember the Bulldozer?). Progress!
    1 point
  35. 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.
    1 point
  36. 4. WinAPI version using ChooseColor function. NativeColors.rar Far from ideal, don't kick too hard. 🙂 Determine Clicked Array Element Index is from here.
    1 point
  37. 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
    1 point
  38. 该文件中有四行头文件 (4 rows of header in this file) 下面是一个程序,它将读取四个标题行,然后每次读取其余的 100 行 read csv per chunk of 100 rows.vi
    1 point
  39. Well, yes and no and yes and maybe. It all depends on what you're trying to measure and what the system requirements are. And, of course, just because it's cheaper up front doesn't mean it's cheaper overall. If it costs $200 less but takes me 50 hours longer to implement then it costs more.
    1 point
  40. New in LabVIEW 2020: C:\Program Files (x86)\National Instruments\LabVIEW 2020\vi.lib\picture\PNG\Draw Flattened Blended Pixmap.vi I didn't create this one. It is not in the palettes. I have asked that it be added in a future version.
    1 point
  41. Here is a VI that gets the title of the window that is active. You could then continually loop until the title you expect is active, then perform operations. https://forums.ni.com/t5/LabVIEW/Get-Current-Active-Window/m-p/3930389#M1116926
    1 point
  42. 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.
    1 point
  43. If you google "LabVIEW modbus" you'll find some solutions. Top one for me was a 2015 article on NI's website.
    1 point
  44. You *can* use DETT on built applications, just enable VI server access and debugging in the build. Here is a description of it: http://digital.ni.com/public.nsf/allkb/A50A8BBFD737679186257D7700688757
    1 point
  45. It's easy, there is probably a vi with that name in memory, so if you would remove the class prefix there would be a conflict. Rename the vi first to something unique and the try to delete it.
    1 point
  46. 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?
    1 point
  47. 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...
    1 point
  48. QUOTE(Tomi Maila @ Oct 30 2007, 01:34 AM) GetValueByPointer takes the C style pointer and the corresponding data type, which are generated by Import Shared Library Tool, as inputs and copies the value which the pointer points in shared library(dll/so/framework) to LabVIEW. Input terminals: Input Type: Input type is the LabVIEW data type to which you want to pass into LabVIEW. Input type can be Numeric, string, Array, Cluster . This VI returns an error if LabVIEW cannot convert the data wired to Pointer to the data type you wire to this input. If the data is integer, you can coerce the data to another numeric representation, such as an extended-precision, floating-point number. Pointer: Pointer is a memory address represented by a 32-bit unsigned integer in LabVIEW. Pack Type: Byte alignment information of the Input Type. Output terminals: Value:Value is the data copied from the memory which is pointed by Pointer and changed to the data type specified by Input type.
    1 point
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