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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

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

In case anyone else runs into the issue...

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.

yes

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.

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?

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?

The Weather Station example that ships with LabVIEW shows a bit of this. but the data is not Base64, its just a pure characters,

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.

You might have more success posting this on the Discord. Most of the conversations happen there these days.

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!

Thanks, I'll be honest, I'm allergic to Discord. Vehemently so. To the point where I refuse to use it. Just seems like a lot of unfiltered noise to this old man. I'm gonna play with NodeRed and see if it's the tool of choice. And oh, back in the day I was a National Instruments Alliance Member. Dunno if that's still a thing or not. Cheers,

This toolkit offer you an efficient, stable, and reliable front panel control value refresh function. User can design their UI dashboard without any code development. 1. Powerful parallel execution capability, Support clone reentrant execution running mode, you can create multi dashboard UIs at the same time and controls can synchronous refresh across different UI. 2. High-speed data refresh capability, even with thousands of controls on a single UI, can easily maintain a refresh rate of 50ms while consuming very little CPU resources. 3. Support all control data types that "Tag Engine" support, this mean the only thing you need to do is to change the control "Label" with "Tag name", then the control will refresh automatically. 4. Support "muParser Expression", you can type the control "Label" with "Expression" that muParser Expression support, For example "a + b" "a > 1 & b >= 2".

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.

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.

Sir, TestStand is developed with C#, and my Sequence Toolkit was developed via LabVIEW from zero, and I posted it on this forum for the purpose of learning and communication. As a LabVIEW enthusiast who had ever worked at NI for several years, I don't understand why you said that.

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:

Discussion forums like LAVA and ni.com are challenged these days by LLMs that can answer in a well structured manner very quickly and handle follow-up questions on the spot. Forums have their stenghts, but when it comes to basic questions that LLMs can find a lot about, spread across multiple forums, the LLMs win. It is a bit of a catch 22 though, as the LLMs need the forums alive to stay up to date 😮 ------------------------------ Here is Grok answering you question of what a DVR is: DVRs as References: In LabVIEW, DVRs (Data Value References) are a mechanism to access data by reference rather than by value. This means that instead of creating copies of the data (as is typical in LabVIEW's dataflow paradigm), a DVR provides a pointer-like reference to a single memory location where the data resides. This avoids unnecessary data duplication, which can be critical for large datasets or performance-sensitive applications. Avoiding Copies: By using DVRs, you can manipulate the same data in memory without creating copies, which is especially useful for large arrays, clusters, or other complex data structures. This reduces memory usage and improves performance. Parallel Operations and Race Conditions: When multiple parallel operations (e.g., parallel loops or VIs) access the same DVR, there is a potential for race conditions if the access is not properly synchronized. LabVIEW provides the In-Place Element Structure to safely access and modify DVR data. This structure ensures that only one operation can read or write to the DVR at a time, preventing race conditions. Without this, simultaneous read/write operations could lead to unpredictable results or data corruption. Key Points to Add: Thread Safety: DVRs are not inherently thread-safe. You must use the In-Place Element Structure (or other synchronization mechanisms like semaphores) to avoid race conditions when multiple parallel tasks access the same DVR. Use Cases: DVRs are commonly used in scenarios where you need to share data between parallel loops, modules, or processes without copying, such as in real-time systems or when managing shared resources. Limitations: DVRs are only valid within the application instance where they are created, and the data they reference is freed when the reference is deleted or the application stops. --------------------- Before DVRs we typically had to resort to cloning of functional globals (VIs), but DVRs make this a little more dynamic and slick. You can have a single malleable VI operate on multiple types of DVRs too e.g., that opens up a lot of nice reuse. If you have an object that requires multiple circular buffers e.g. you can include circular buffer objects in the private data of that object, with the circular buffer objects containing a DVR to an array acting as that buffer... -------------------- Here is ChatGPT comparing functional globals with DVRs: Functional Globals (FGs) and Data Value References (DVRs) are both techniques used in programming (particularly in LabVIEW) to manage shared data, but they offer different approaches and have different strengths and weaknesses. FGs encapsulate data within a VI that provides access methods, while DVRs provide a reference to a shared memory location. Functional Globals (FGs): Encapsulation: FGs encapsulate data within a VI, often a subVI, that acts as an interface for accessing and modifying the data. This encapsulation can help prevent unintended modifications and promote better code organization. Control over Access: The FG's VI provides explicit methods (e.g., "Get" and "Set" operations) for interacting with the data, allowing for controlled access and potential validation or error handling. Potential for Race Conditions: While FGs can help avoid some race conditions associated with traditional global variables, they can still be susceptible if not implemented carefully, particularly if the access methods themselves are not synchronized. Performance: FGs can introduce some overhead due to the VI calls, but this can be mitigated by using techniques like inlining and careful design. Example: An FG could be used to manage a configuration setting, with a "Get Configuration" and "Set Configuration" VI providing access to the settings. Data Value References (DVRs): Shared Memory Reference: DVRs are references to a memory location, allowing multiple VIs to access and modify the same data. This is a more direct way of sharing data than FGs. Flexibility: DVRs can be used with various data types, including complex data structures, and can be passed as parameters to subVIs. Potential for Race Conditions: DVRs, like traditional globals, can be prone to race conditions if not handled carefully. Proper synchronization mechanisms (e.g., queues, semaphores, or action engines) are often needed to prevent data corruption. Performance: DVRs can be very efficient, especially when used with optimized data access patterns. Example: A DVR could be used to share a large array between different parts of an application, with one VI writing to the array and another reading from it. Key Differences and Considerations: Control vs. Flexibility: FGs offer more control over data access through their defined interface, while DVRs offer more flexibility in terms of the data types and structures that can be shared. Race Condition Mitigation: While both can be susceptible, FGs can be designed with built-in synchronization mechanisms (like action engines), while DVRs require explicit synchronization mechanisms to prevent race conditions. Performance Trade-offs: DVRs can offer better performance in many cases, especially when dealing with large data sets, but this can be offset by the complexity of managing synchronization. Code Readability and Maintainability: FGs can make code more readable and maintainable by encapsulating data access logic, but poorly designed FGs can also lead to confusion. In summary: Use Functional Globals when: You need controlled access to data, want to encapsulate data management logic, or need to ensure some level of synchronization. Use Data Value References when: You need to share data efficiently between multiple parts of your application, need flexibility in the data types you are sharing, or when performance is critical and synchronization can be handled externally. It's worth noting that in many cases, a combination of both techniques might be used to leverage the strengths of each approach. For example, a DVR might be used to share data, while a functional global (or an action engine) is used to manage access to that data in a controlled and synchronized manner.

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

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

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

Another VI I thought someone reading this forum thread might find helpful. This one calls the one I posted previously as a subVI. "Make Control Glow.vi" draws a fading rectangle behind the specified control. Save it and its subVI ("Offset Glow Rect.vi") to the same subdirectory. For example, here's a glow on a system OK button. Color and border thickness are parameterized. Saved in LV2020. Make Control Glow.vi Offset Glow Rect.vi

Not from NI, that I know of. I did make a similar API that wraps the Qt framework. That involves creating external windows though; your toolkit has the benefit of being integrated with VI front panels. Original LAVA post: https://lavag.org/topic/19611-utf-8-text-svg-images-inheritable-gui-components-dynamically-composed-guis-layout-management-splitters-in-tabs-mdis-taskbar-integration-and-much-more/ NIPM installation instructions: https://jksh.github.io/LQ-Bindings/docs/ As Mikael and Rolf said, class constants are not needed: Definitely! LabVIEW's built-in support for dynamic GUIs is very poor. NXG was starting to show some promise with dynamic controls, but that's now dead. So, community-built tools are sorely needed. Are you planning to make public releases of your work? Layouts are common concept in a wide variety of GUI toolkits. Makes it so much easier to create resizable GUIs and support a variety of screen resolutions.

MAT files are now just H5 files(HDF). Look at the library https://h5labview.sourceforge.io/ and find the example for writing a MAT file. You just need to add a special header in the beginning. I assume the dlls needed will work on Windows server, but am not sure.

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

This seems to work... CRC16-CCITT-FALSE.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).

Here is a quick and dirty edit. It allows for column separators to be moved, but I noticed that on resize it will set the column widths. So this means if you manually move the columns, and then resize the control it may change the columns in an unexpected way. But at that point you can manually move the separators again. I only have 2017 and 2018 so this is for 2017 and newer now. Variant_Probe-2.4.3-0.ogp

I love the Picture Control, it's very fast if you use it correctly. I developmed the whole GDS UML modeller (http://opengds.github.io/) based on that. One performance issue is if you draw lot of text with a none default font size, then it becomes very slow. Make sure you use Smooth updates, and I always use Erase first. What does the shft register make it poorly? Do you have an exmaple where it's slow we can look at?

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.

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.

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 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...

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.