Questions tagged [labview]

LabVIEW stands for Laboratory Virtual Instrumentation Engineering Workbench and is a graphical programming system by National Instruments. The programming language is called G but often referred to as just LabVIEW.

LabVIEW is a graphical development environment offered as proprietary software by National Instruments and complementing their industrial controllers and data acquisition systems used in research labs and elsewhere.

The programming language itself is called G but usually referred to as just LabVIEW. The programming language is a parallel, dataflow, graphical, type-safe language. Dataflow provides automatic memory allocation/deallocation without the overhead of garbage collection. The language includes hooks to call into native C, .NET, COM, etc.

A LabView application is represented by a so-called "virtual instrument" or VI. A VI is divided into two parts: the front panel and the block diagram. The front panel acts as the GUI and defines the user interface where all the visual elements ("controls") are drawn and placed. Front panel controls include buttons, switches, knobs, and so on. Output elements like graphs, thermometers, and text boxes are also placed on the front panel.

The block diagram contains the execution code. LabVIEW code follows a dataflow-based execution paradigm. Functions are represented as individual blocks on the block diagram, with each function having zero or more inputs and one or more outputs. The dataflow programming paradigm dictates that a block (function) cannot execute until it has received data on all of its inputs, and a block outputs data on all of its outputs simultaneously once it has executed. Each block is, from the perspective of the block diagram in which it resides, atomic. Wiring determine execution order between blocks, and sections of a block diagram that share no connections can run completely in parallel.

To include LabVIEW code in your question, consider using a VI Snippet so that others can view, run and edit your code.

You can read more on the LabVIEW wiki or on the official National Instruments website.

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What is error code 0x800A01A8 coming out of Excel ActiveX call?

I am using LabVIEW to talk to Excel via its ActiveX interface. For some reason after some time successfully writing to a spreadsheet I got this error when attempting to call the a function which does something with the range. Sorry this question is…
user189471
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Python list to XML and vice versa

I have some python code that I wrote to convert a python list into an XML element. It's meant for interacting with LabVIEW, hence the weird XML array format. Anyways, here's the code: def pack(data): # create the result element result =…
ctrlc-root
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Track position of a Zaber device as it moves

I'm writing a LabVIEW VI to move a Zaber linear actuator, and I want to record the device's position every few milliseconds as it moves. I've installed Zaber's LabVIEW driver and used its examples to get my actuator moving, but how can I read the…
Don Kirkby
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Setting the value of an array control of a Labview VI through ActiveX (with Matlab)

I have a Labview VI that I intend to run from Matlab through ActiveX. It has one argument (that is, one Labview control), which is of type 1D numeric array. The method used to call the VI from Matlab through ActiveX is detailed in a previous post. I…
calvin tiger
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How do I capture live video from my webcam using labview 2011?

I was wondering if it would be possible to capture the live video from my integrated webcam using Labview 2011(National Instruments). All I need to do for now is put the camera in the front panel. This is not a USB Webcam. It is a chicony USB 2.0…
Josh Menzel
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OLE automation problems with C++ - "Class not registered"

I'm trying to port a LabView program to C++, and the OLE calls it contains are giving me some trouble. The LabView program starts out by doing an "Automation open", i.e. getting a reference to the interface "XLib.XInterface" (LabView calls this…
xqrp
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how to read write labview network shared variable from c++

LabVIEW gives the possibility of sharing variables over the network. I would like to be able to read and set those variable from my C++ code. (I run under linux system) I read there are some DLL API for communication but of course they do not fit my…
Stefano
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Problem in returning images in Python for LabVIEW

I am just starting to learn LabVIEW. I want to get a threshold from my image in a python function and display the image in LabVIEW. But when the function returns the image, it gives an error in LabVIEW. I am sending the relevant code in Python and…
Saberi
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INFORMATION_SCHEMA.COLUMNS sorted alphabetically initially, then a few days later sorted by ORDINAL_POSITION

After MySQL 8.0.25 (InnoDB engine on Windows) upgrade from MariaDB (10.1.26, and I don't think we were using InnoDB engine on Linux), every time our DB server restarts, we run into this issue: SELECT * INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME =…
oudent
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Is there a way to generate random numbers between 0 and 500, but if first number is 300 not to deviate more than 20 for the next?

Is there a way to generate random numbers between 0 and 500, but if first number for example, is 300, not to deviate more than 20 for the next? I don't want 500 then 0 then 399 then 1. Thanks.
alienware13user
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LabVIEW - can you use a numeric control as an indicator

I've written LabView code for a locking system. The lock has a motion timer that relies on input from a numeric control. I've added a script file reader that needs to be able to change that timer value. Using a selector, I can switch between values,…
Jedi Engineer
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User input range for XY graph

I'm a beginner user of labview so bear with me, please. I'm working on a project that takes a data text file with columns and rows as an input. I have the project set up so far to take the data from that file and display it in an XY graph. I want…
Ahmed
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Dynamically set maximum scale of horizontal pointer slide in labview?

I want to make a primitive movie player in Labview. I want the user to be able to load in a movie and have a slider to select frames. As such, I want the range of the slider to go from zero to N where N is the number of frames in the movie. How do…
AndyL
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Multiple plots to same chart in LabVIEW

I am doing a two-channel data acquisition to read out the voltages of two diodes. I am using LabVIEW to do this. Below you can see the part of the code relevant for my question. The voltages are converted to temperatures by 1D interpolation, as…
zeus300
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How to quickly unpack U32 Image Array into an RBG U8 Array in LABVIEW

I have a flattened (1D) U32 encoded image array which has r, b, and b 8-bit channel values encoded into the first 24 bits of each U32. I would like to expand this array into and array of U8s that each store a separate r, g, or b value (0-255). The…
Alec Graves
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