Converting Dynamic ECG to Arrays

Hi, im new to this forum and LABView program.
I am doing an HRV analysis using LABView for a project in school, with the help of the NI developer's Zone HRV guide.
All are good while using a static .txt array for the input, but now i need to get a dynamic signal using a DAQ and an ECG simulator, and i am unable to write the DDT to arrays.
I have search the site for other people's query on this matter, but none of the method work on my program.
Anyone with around care for a help? I have i picture of my program uploaded:

The first thing to do is put your data acquisition and this code inside a while loop so that it run more than once. Then you can place a shift register on the while loop. Right click on the edge of the while loop and select Add Shift Register. Shown below is the basics.
Attachments:
Basic Shift Register.PNG ‏5 KB

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How can i convert object to byte array very*100 fast?

i need to transfer a object by datagram packet in embeded system.
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but, it's not satisfied my requirement.
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Using ObjectOutputStream is very slow, so i'm using this way.
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Edited by: JongpilKim on May 17, 2009 10:48 PM
Edited by: JongpilKim on May 17, 2009 10:51 PM
Edited by: JongpilKim on May 17, 2009 10:53 PM

thanks a lot for your reply.
now, i use udp socket for communication, but, i must use hardware pci communication later.
so, i wrap the communication logic to use jni.
for convert a object to byte array,
i used ObjectInputStream before, but it was so slow.
so, i change the implementation to use byte array directly, like ByteBuffer.
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public class PacketData {
priavte int a;
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helper.putInt(b);
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but, it's not enough.
is there another way to send a object data?
in java language, i can't access memory directly.
in c language, if i use struct, i can send struct data to copy memory by socket and it's very fast.
Edited by: JongpilKim on May 18, 2009 5:26 PM

How do I convert a 1-D array of cluster of 5 elements into a 2-D array of numbers? (history data from a chart)

Hello,
in my vi I have a chart with 5 Plots displaying measurement data.
The user should be able to save all the history data from the chart at anytime. (e.g. the user watches the chart and some event happens, then he presses a "save"-button)
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Johannes
Greetings Johannes
Using LabVIEW 7.1 and 2009 recently
Solved!
Go to Solution.

Gerd,
thank you for the quick response and the easy solution.
Look what I did in the meantime. I solved the problem too, but muuuch more complicate :-)
And I have converted the numbers to strings, so that I can easily write them into a spreasheet file.
Johannes
Message Edited by johanneshoer on 04-28-2009 10:39 AM
Greetings Johannes
Using LabVIEW 7.1 and 2009 recently
Attachments:
SaveChartHistory.JPG ‏57 KB
SaveChartHistory.JPG ‏57 KB

Converting object wrapper type array into equivalent primary type array

Hi All!
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Is sound like a trivial task however the problem is that I do not know the type I work with. To understand what I mean, please read the following code -
//Method signature
Object createArray( Class clazz, String value ) throws Exception;
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Unfortunately I was unable to find any useful method in Java API (I work with 1.5).
Did I make myself clear? :)
Thanks in advance,
Pavel Grigorenko

I think I've found the answer myself ;-)
Never thought I could use something like int.class or double.class,
so the next statement holds int[] q = (int[])Array.newInstance( int.class, 2 );
and the easy solution is the following -
Object primeArray = Array.newInstance( token.getPrimeClass(), split.length );
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Convert variable into an array

I have variable, abc; whose value is in the format val1,val2,val3,..
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examine this class that I did
import java.lang.*;
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Convert Dynamic Disk to Basic Disk Witout Data Loss

I think I goofed somewhere and am in need of some advice.
This Windows 8.1 home server had two identical 160GB drives that at one point were mirrored. One of the drives failed but so I added a larger replacement hard drive (Disk 0 = 160GB, Disk 1 = 250GB) and was able to recover. However now, not only
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See:
How to Convert Dynamic Disk to Basic Disk without Data Loss?
Carey Frisch
Thanks for the reply.
I've seen that post, among others, and they all require buying an application. None of the product pages, like the one you linked indicate that a purchase is required. It wasn't until I downloaded the aplications, (and I've tried several) that
I discovered a purchase was required. Really disappointed they weren't upfront about that on the guides.
So maybe a different approach can be taken:
Disk 1 just contains the System Recovery partition - the rest of the disk is blank (not partitioned)
Create a new partition
Copy the OS data from Disk 2 to Disk 1
Update the System Recovery and/or the Boot Configuration Data file to point to the OS that's now on Disk 1
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Convert Disk 2 to a basic disk
Once Disk 2 has been converted back to a basic disk, can I just do the opposite?
Create 2 partitions on Disk 2: one for System recovery and another for OS
Copy the System Recovery partition (partition on Disk 1) to partition 1 of Disk 2
Copy the OS partition (partition 2 on Disk 1) to partition 2 of Disk 2
Update the System Recovery and/or the Boot Configuration Data file to point to the OS that's now on Disk 2
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Convert Disk 1 to a basic disk
This is bonkers, believe me, but I feel silly shelling out $40-$50 for a single feature of an application. If I were going to use it regularly, or even periodically, I would do it.
I'm not very comfortable with bcdedit and bootrec so I need a little help with steps 4 in both sections.

Converting String to byte array

Hi,
There is a code for converting String to byte array, as follows:
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Thanks.

> In fact, I tried with String.getBytes() too, but leads to the same problem, with those specific symbols.
Did you try the String.getBytes(String charsetName) method?
Both methods have been around since Java 1.1.
It's an extremely important skill to learn to read the API and become familiar with the tools you will use to program Java. Java has an extensive set of online documentation that you can even download for your convenience. These "javadocs" are indexed and categorized so you can quickly look up any class or method. Take the time to consult this resource whenever you have a question - you'll find they typically contain very detailed descriptions and possibly some code examples.
Java� API Specifications
Java� 1.5 JDK Javadocs
Best of luck!
~

How to convert from XML to Array ?

how to convert from XML to Array ?
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this is a segment of the xml object:
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<task>
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For dynamically allocated double arrays, sizeof() does not work

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Go to Solution.

That's because sizeof(myArray) is the size of the pointer to the dynamically allocated array.
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Hi
I am doing my M.Tech Thesis in Image reconstruction and I am using labview for simulation and I want to know how to store the output of a analog to digital converter into an 2D labview array.

nitinkajay wrote:
I want to know how to store the output of a analog to digital converter into an 2D labview array.
How exactly are you performing 'Analog to Digital'???
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Steve Chandler wrote:
If you remove the first and last byte from the string using string subset then the read spreadsheet string would probably have worked.
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String to Array ExampleMOD2.vi ‏10 KB

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Thanks for responding.
I have however arrived at a solution. A little un-elegant but it seems to do the job.
I am converting each byte into char manually by this algorithm:
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Convert digital waveform to array

Hello,
I posted a problem before Christmas regarding data acquisition and accessing the hardware buffer on a 6562 card. I managed to figure out that problem but now I'm stuck when I try manipulating the data I obtain. (The original problem can be seen here: http://forums.ni.com/ni/board/message?board.id=70&thread.id=7926)
Briefly, my application is clocking and synchronising an ADC board and then looking at the raw ADC data that comes back from the board. To provide synchronisation I am sending a sync pattern on one data line and using a second line to send a "start of frame" indicator, a '1' bit when I know that the board is synchronised. This line otherwise only sends ‘0’s. This cable is wired back into the NI card and LabView. All data sent uses the NI-SHDIO Generation Express VI and I'm using the Acquisition Express VI in parallel with the Generation VI to capture the raw ADC data when it comes off the ADC board. Since I am acquiring both the ADC data and the frame indication data (which I am looping by connecting that output DIO to an input DIO), the digital waveform essentially contains 2 arrays and I can view these from a graph indicator within LabView.
No problems so far. In order to manipulate the data and look at individual frames I am writing the ADC data to file. To extract the digital data from the digital waveform I am using the following VIs:
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To view and manipulate the data I read it into Matlab and this is where I can tell that something's not right. When I read the file into a variable in Matlab, the variable becomes a 1D double array of 40,008 elements. This seems very odd, considering the Acquisition VI only takes 20,000 samples. When I look at the 1D array more closely it looks like the two arrays have been cross added in some fashion. The 1D array certainly doesn't match either of the two arrays visible in the graph indicator inside LabView. I can understand if the file is reading one array after the other (20,000 + 20,000 almost equals 40,008 after all) but that doesn't appear to be the case.
I would greatly appreciate some help on how I can extract the two data lines either using Matlab or LabView. Currently it looks like LabView is making a hash of things whenever I try to manipulate or extract the two arrays from the digital waveform. I have tried a multitude of different VIs and ideas but nothing appears to work.
The most straight forward way would be using the "Converting Digital Waveform to Binary VI" but it can't handle two arrays within the same waveform. (The result looks like the two arrays exclusively OR’d together). To combat this I tried running two Acquisition Express VIs in parallel (one for ADC data, the other for the frame info) but got an error message referring to invalid handles. I presumed this meant that I can't run two acquisition VIs simultaneously, judging from forum posts of users facing the same error message.
Sorry for the long post but I feel that I needed to fully explain the problem. I'm attaching my LabView code.
Thank you for reading,
Christian
PS. GenAcq2.vi is my code. Waveform_GenAcq2_Cfg.hws is sent by the first Generation VI; Waveform_GenAcq2_shorter_frame_indicators.hws by the second Generation VI.
Attachments:
CodeAndWaveforms.zip ‏126 KB
GenAcq_Screenshot.JPG ‏83 KB

The extra "8" is being caused by the fact that the "Write to Binary File" VI has a "prepend array or string size" input. Its default is true, and in your case you have it unwired, so you get the array size prepended. As for the rest of your issue, what are your Matlab commands to read a file? The following example VI, which generates a digital waveform and saves it to file,
can be correctly read into Matlab using the following commands:
fid = fopen('c:\temp\digData.bin','r');
F=fread(fid, [256,8], 'uchar');
Message Edited by smercurio_fc on 01-18-2008 05:26 PM
Attachments:
Example_VI_BD.png ‏11 KB

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How can I convert values in a vector into a string array?
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Converting Dynamic ECG to Arrays

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