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Nadaraya-Watson estimator in LabVIEW

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I like the Nadaraya-Watson (NW) kernel regressor because it allows discrete windowed linear smoothing on non-uniformly sampled data without explicitly presuming a fit function.

 

It is a "non-parametric" approach and that means it has a different set of assumptions about the basis than typically "parametric" approaches.  It " in finite samples the NW estimator tends to have a smaller variance" than expectation-maximization methods. 

 

Is there an estimator built into LabVIEW that has equivalent or greater performance?

 

Some references:


Matlab function refuses to run in the mathscript

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Hi,

I tried to run a function.m (call_osc) that calls another function.m (osc).

It is working and plotting perfectly in matlab but when I I include them in mathscrip window after adding the 2 functions in the appropriate folder I get an error saying that y in unknown.

I tried also to add both functions in the mathscrip structure. But no success.

Could someone help me to solve this problem, please?

It will be great if I have all the code together in one windows instead of calling different functions.

Thanks

Event structure in event structure

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Is there a way I can have an event structure which is in another event structure? When I run the code, I can't operate other buttons. (See diagram for clarification) 

 

EventStructure.png

Choose ISE or Vivado Xilinx tools for a specific FPGA compilation

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Hello,

 

Is there a way to specify which version of Xilinx Compilation Tools to use when compiling an FPGA VI? I want to try the Vivado version of the tools rather than the ISE version to see if there is any improvement. I've listed some information about my setup below.

 

This is my current setup:
NI5772 / PXIe7966 digitizer and FPGA
PXIe-1082 chassis
PXIe-PCIe8388 / PXIe-PCIe8389 controller
LabVIEW 2014

 

In the past I have used the 'LabVIEW 2014 FPGA Module Xilinx Tools 14.7' to compile my code. But I also want to try the Vivado version, 'LabVIEW 2014 FPGA Module Xilinx Tools Vivado 2013.4', to see if it gives better results.

 

Based on the 'Compatibility between Xilinx Compilation Tools and NI FPGA Hardware' page here:
http://www.ni.com/product-documentation/53056/en/
It looks like the PXIe7966 FPGA should be compatible with the Vivado 2013.4 tools. 

 

I have tried uninstalling the ISE 14.7 version of the tools, and installing the Vivado 2013.4 tools (so that the Vivado 2013.4 tools are the only xilinx tools installed on the computer). But LabVIEW still complains that the ISE 14.7 tools are not installed and does not compile the FPGA VI.

 

Thanks!
Michael

Best Practices for writing data to a network drive?

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Historically I've just written data to the local hard drive on the test PC to prevent LabVIEW from locking up if the PC happens to lose network connectivity for whatever reason. However, for multiple reasons (redundancy, remote monitoring, etc.) it would be ideal for our test program to be able to write this info to a network drive location.

 

My question is, what are some Best Practices for accomplishing this? How have you overcome the inevitable loss of network connectivity? Is there a way to have LabVIEW buffer the data while continuing to test and then write it to the network once it has come available again...without freezing up? Are there any existing VIs that can handle this? I don't want to have to re-invent the wheel!

 

Additionally, it would be really nice if LabVIEW could figure out how to continue writing to a CSV or XLS file even though someone has the file open in another program. I can't even count the number of times I've had a test program crash because I forgot to close out of the datalog file in Excel before re-starting a test...nevermind that I was only LOOKING at the file and made no changes to it.

Pausing execution of a VI

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Hello I have a question regarding waveform chart that is generated with the time stamp on the x axis, the time stamp is in Hours:MinutesSmiley Frustratedeconds format, assume the graph is flowing on an x axis range of 12 seconds. If the VI started running at time stamp 10:00:00am and the waveform started showing data from this time to time 10:00:05 and then the VI was paused "the acquisition will be paused at the 5 seconds mark" after that the VI was resumed after a 1 minute wait ,will the waveform x axis show a new time stamp or will it resume from the 10:00:05 till the end of the range as normal i.e will it continue from 10:00:05 or 10:01:05
i hope you understood my question

help with mean filtering and noise reduction with Mathscript

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Hello, I have this:

 

The idea of mean filtering is simply to replace each value in a signal with the mean (average) value of its neighbors. A mean filter is widely used for noise reduction.

Start by adding some random noise to a signal (use the file echo_1.wav or any other speech data file). Then, use mean filtering to reduce the introduced noise. More specifically, take the following steps:

  1. Normalize the signal values in the range [0 1].
  2. Add random noise to the signal by using the function randn. Set the noise level as a control.
  3. Convolve the noise-added signal with a mean filter. This filter can be designed by taking an odd number of ones and dividing by the size. For example, a 1× size mean filter is given by [1/3 1/3 1/3] and a 1×5size mean filter by [1/5 1/5 1/5 1/5 1/5]. Set the size of the mean filter as an odd number control (3, 5 or 7, for example).
 

Help Needed for an Application Recording and Storing Values in an Array

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Hi

 

Hope this explanation isn't confusing. I've explained my desired application in text below,and also attached a skeleton VI + screenshot hoping it will clarify


I'm attempting to make a VI that does the following:
1. Some code (blue SubVI) runs every 200ms
2. Every 200ms a random number is generated
3. The random numbers are stored in an array in time intervals of 0.8s ("iterations")
4. At every point in time, the code (blue SubVI) needs to have access to the random numbers that were generated in "the previous iteration"

To clarify, the iterations are as follows:
Iteration #1: 0-1.8s
Iteration #2: 2-2.8s
Iteration #3: 3-3.8s
..
And so on..

So for every iteration: the code (blue SubVI) needs to have access to the random numbers that were generated in the previous iteration, for example:

Iteration #1 (0s-1.8s): The code (blue SubVI) gets an array containing only zero's (random numbers are recorded for the first time)
Iteration #2 (2s-2.8s): The code gets an array containing random numbers from iteration #1
Iteration #3 (3s-3.8s): the code gets an array containing random numbers from iteration #2
Iteration #4 (3s-3.8s): the code gets an array containing random numbers from iteration #3
..
And so on..

At any given point in time;
- The code is being fed an array containing all random numbers recorded during the previous iteration
- Values from before the previous iteration are discarded and not stored anywhere

 

So for example, at iteration #7:

- Values recorded during iteration #6 are being made available to the code in the form of an array

- Values from iterations #1 to #5 have been deleted and are not stored anywhere



It's important that all values recorded from before the previous iterations are deleted as they are not needed as the actaual VI will be running for a long time storing much more numbers than what I have indicated here

 

Screenshot of the Skeleton VI:

Iteration_Scheme_PNG.png

I've tried playing around with arrays, case structures and shift registers, but every time I try I end up doing something wrong

 

The Skeleton VI is also attached (Iteration_VI, and Code_SubVI)

 

Any suggestions?

 

Thanks!


labview RT addon installed but not present

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Hello,

 

I had LabVIEW 2014, 2015 and 2016 Beta test version installed on one of my PCs (all 32bit versions). I had also LV RT installed on the LV 2016 Beta. I uninstalled LV 2014 and 2016 beta and all associated modules. Restarted PC. Installed the official LV2016, PC restart. Installed LV2016 RT, restart.

 

Now I do not have RT accessable from LV2016. When I start LV, the RT "logo" is also not shown, and I cannot access RT VIs and functions. I tried to repair the RT installation, no success. What else should I try in order to use RT from LV2016? Here is the licence manager state now:

 

sdgdegr.png

 

How to implement Savitsky-Golay Filter on FPGA

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Hi,

 

I am implementing my control algorithm using Compact RIO-9022, and I have to know the velocity and acceleration from the position signals (1st and 2nd derivative of position).

 

I have used the Savitsky-Golay filter to calculate derivatives and smooth signals in Scan mode, and it performs a nice job. But the max scan speed is too slow, scan period >=1ms, in this mode.

 

So, I am transferring files to FPGA style. But there is no exsiting S-G VIs like in scan mode.

 

Is there any advance to implement S-G filter on FPGA for beginner? or is it possible?  

 

Thank you in advance.

Wang

 

Trying to get back into Labview - Where do I begin?

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Hi all

 

I use to work in the Automotive Industry in the UK last year. I been a QA Tester for over five years with an ISTQB certificate as well.

 

Towards the end of my last months working there, they told me they were going to let some people go which included me unfortunatly. However, I asked my manager if I can learn about Automation and he said I could work with the Automation guys. Lo and behold, they used Labview. The Labview staff I briefly worked with were really nice and I just wished I could have stayed there much longer.

However, the problem was I wasnt given enough time to grasp the general knowledge of Labview. But from what I can gather from the situation at my workplace without giving out too much information about the company I worked for, for Automation they used a camera to compare all previous test of the screen. So for instance, it could tell if the speed of the screen was slower and had misalign borders around the screen from previous results. And he also had a standard excel spreadsheet for running tests.

What areas of Labview does everyone think they cover? Its something I want to try and match at home if possible.

 

When I left my last work place, I was advised by the Labview engineer I worked with who told me I should learn a coding Language. He said it could be anything live Java, Ruby etc. I am doing some Java coding whislt job hunting and I did some Ruby coding years ago but I might need a refreasher.

 

I am not sure how all this fits in with Labview but as you can tell, I am coming at Junior level hoping to learn more. I really need some advise on what I should do. I feel clueless on what I did at my last work place and I want to better my understanding. I was looking at taking up one of the Labview certs but how did everyone else landed a job with using Labview equipment.

 

Thanks in advance.

scanning for keyFocus to set Boolean background color

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I searched for "ctl class colors[] property" before posting.

 

I've changed Boolean background colors via their individual colors[] propertiy but I was wondering if there's a way to scan controls[] refnums and set the background colors based on key focus True/False.

 

See the snippet. I don't see a background colors property in the ctl class. Is there another class beneath 'ctl' that allows one to set Boolean colors[] property?

 

Thanks,

3D Picture: Create Cylinder. Wireframe options?

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Application: I've built a pretty good device that images the contents of a cylindrical container in 3D. I want plot a cylinder around the 3D structures to give context in the resulting images and movies the system generates.

 

Problem: I'm using the 3D Picture functions. The native Create_Cylinder.vi allows a couple of options. Unfortunately, a solid cylinder would obscure the data. The wireframe option also obscures the data, while the 'Points' option doesn't really look like a complete cylinder to the untrained eye.

 

I've mocked up what I am looking for in Solidworks in the attached image.

 

I'm hoping there is a built-in way to do what I am wanting, otherwise it seems I'll have to use camera position and cylinder coordinates to calculate where the perceived edges would be and then draw lines there. 

 

LabVIEW Professional Development System 2012

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Please advise the link to download 2012 LabVIEW Professional Development System. I

LabVIEW Professional Development System 2012

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Please advise the link to download 2012 LabVIEW Professional Development System. 


Array size of empty array - bug

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I have 2 empty arrays with different sizes

How can I set a deadband for PID control

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when I use a PID.Vi to adjust a pressure, when the PV close to SV, I want the PID.vi hold its output,but I have no idea to set the deadband parameters! (can not find how to set dead band )

PID.jpg

 

WAVE.jpg

A PLC engineer said that   deadband is a common PID  parameters ,but Idon't know how to set it in labview pid !

Help ,please,thanks!

 

myRIO - ICS43432 MEMS microphone

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Hello everyone!

 

I'm currently using the ICS-43432 MEMS Mic and would like to find out what's the maximum number of such microphones that can be interfaced onto the myRIO unit (:

 

Many thanks

Bellywellyjelly

Create a matrix whose diagonal elements are determined by a control

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Hi,

 

How can I create a diagonal matrix whose diagonal elements are determined by a control?

 

Like  [ lamda 0; 0 lamda]

 

Thanks in advance.

Chuan

Mistake 1073807302 by using VISA Read

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Hello,

I want to communicate with a photometer, that used a HID interface. The device use a PIC24FJ.

The photometer is new (published in the last month) and the interface protocol isn´t published yet, but I got a preliminary version from the producer.

I created a driver by using VISA Driver Wizard and the device is in MAX visible.

Now i can use "VISA Write" and the device react to the commands, but it isn´t possible to read the data from device. 

Mistake No. 1073807302

When I try to read the data by using the VISA test panel in MAX I get a "Read Operation Error  0xBFFF003A".

 

Also I tried to communicate by using mcHID.dll (Link), but LabVIEW always crashed.

 

I attached my VISA Test VI.

 

Have anyone an idea, which can solved my problem?

 

Stefan

 

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