Arrays to bundles?

Hey..
I have 4 data points in an array that I wish to display as separate plots
on a
chart. Do I need to change this array into a bundle, or is there another
way of doing this?
Thanks

don't worry - i think I figured it out!
"amie" wrote:
>>Hey..>I have 4 data points in an array that I wish to display as separate
plots>on a >chart. Do I need to change this array into a bundle, or is there
another>>way of doing this?>>Thanks

Similar Messages

How to find out and locate the top 100 max elements from a 4D array

I try to find out the 100 maximum elements in a 4D array and then I want to put the result in a 2D array, Which should show me the locations of the elements and the values of those elements
====================
=Labview 7.0 & 8.0 & 8.5=
=====================

Hi,
Don't know why you want a 2D array, this VI puts the results in a bundle.
Just because it seems more practical to me (there's less room for
mistakes)...
The VI works as follows:
The max value is returned, incl. it's index.
Then it is replaced by the original minimum value, minus one.
If the last found maximum is the (original) minimum, everything is skipped.
If you really want a 2D array, instead of a bundle, replace the contant with
an empty 2d array, the bundle with a build array, and the indicator with a
2d array...
Regards,
Wiebe.
"asd iyvjh" wrote in message
news:50650000000800000017AC0000-1066448259000@exchange.ni.com...
> I try to find out the 100 maximum elements in a 4D array and then I
> want to put the result in a 2D ar
ray, Which should show me the
> locations of the elements and the values of those elements
[Attachment Max 100 Values From 4D Array.vi, see below]
Attachments:
Max_100_Values_From_4D_Array.vi ‏45 KB

Updating data from a text file in DW is it possible ?

Hello,
I would like to know if there is a way to update
info that I originally input into DW from a .txt file
using the insert tabular data command.
If anyone know if this is possible, I'd really appreciate
knowing this. I don't mean via means of using php, or anything like
this.
I am talking about updating info in cells on a local
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Thank you for any info

It really depends on how you've saved the data. If you have a simple text file with x data in one column and y data in another, then you can use the code below. It's just a Read From Spreadsheet File, and Index Array, and Bundle function. Modify as needed for your actual data. If you get stuck, post a small example of your data file.
Message Edited by Dennis Knutson on 09-17-2008 11:10 AM
Attachments:
Read XY Graph.PNG ‏3 KB

Plotting data from a text file in LabView 7.1

This my be a stupid question, but here is goes. Working with another person, far more LabView experience than I, a VI was created to take data and output it on the screen, real time, as an x-y plot. Once the test was completed the data was stored in an .txt file which could be read into Excel. Now the end user wishes to read the old data back into Labview with an x-y plot of the data, the same way it was displayed during the test. Before I started to pound my head against the wall, thought I would ask this to the group. Everyone has been very helpful in the pass, so hopefully this will be an easy question for the group.
The question is how do I import a text file into Labview and plot it on an x-y screen?
Thanks,
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It really depends on how you've saved the data. If you have a simple text file with x data in one column and y data in another, then you can use the code below. It's just a Read From Spreadsheet File, and Index Array, and Bundle function. Modify as needed for your actual data. If you get stuck, post a small example of your data file.
Message Edited by Dennis Knutson on 09-17-2008 11:10 AM
Attachments:
Read XY Graph.PNG ‏3 KB

How do I get live data from a subvi while it is running ?

Hi.
I'm finishing up my little application, and one of the things I cant figure out to get to work is getting live data from a subvi and displaying it on my main vi's front panel.
In my subvi I am sending about 10 commands to the serial port, each time updating a local variable that writes value to a progress indicator. I would like to get that indicator displayed on my main vi so I can see the progress of my subvi.
Currently I have just linked the progress indicator on the sub to a terminal, and connected that to my main vi, but, that only updates when the sub finishes its mission. Is there a way to update the main while the sub is active ?
Any ideas appreciated !
/Brian

In your VI Prg_all_sub, you are actually only writing out the progress bar once to the contol reference. Once the code to the top has executed, it will never execute again although you continue to write values to the local variable PP throughout the program.
The quickest fix would be to put that code at the top in a loop with a small time delay function. That way it continues to execute every time a new value gets written to the local variable. You would have to use a local variable stop button to stop hat loop wonce your string of VISA reads and writes executes. Also make sure to reset that stop boolean to false once the loop ends so that the loop will execute properly the next time this sub VI is called.
Other recommendations for cleaning up the programming is to use arrays or bundle values into clusters that you pass into and out of subVI's. Prg_all_sub and MPS setup loader have numerous wires going into and out of the sub-VI's. Bundling these together would simplify the wiring quite a bit.
Note also that in a lot of places you send in a wire to an indicator and branch it off to a local variable of the same indicator. That is redundant. Sending the wire to the local variable does the same thing as sending the wire to the indicator. Try to use wires instead of local variables as much as possible. For instance, near the top you send the output of the VISA resource name control back into a local variable of itself, (not necessary) then use a local variable numerous times in the case structure below. Just wire the name into the case structure border, and maintain the value through all of the loops using a shift register. This will eliminate dozens of copies of the VISA resource name variable.
In several places you concatenate a carriage return character to a string constant. Just put a "\r" at the end of the string constant when it is shown in \ display. Then you can eliminate the concatenation.
I hope this helps you get your progress bar working and help simplify the code for you.
Message Edited by Ravens Fan on 08-13-2007 09:34 AM

Non uniform intervals in the X-axis of LineChart

Hi,
I am using a Flex3 Line chart which takes data from an External XML file.
But I dont get the DataTip points correctly if i give some numeric values in the X values and
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How to have the uniform intervals in the X-axis so that the DataTip shows correct values as in the data?
Below is the MXML & the XML I use:
The MXML:
<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" width="100%" backgroundColor="0xFFFFFF" creationComplete="fetchData();">
<mx:HTTPService id="myServ" url="TempChartData.xml" fault="faultHandler(event)"/>
<mx:Script>
<![CDATA[
     import mx.controls.Alert;
     import mx.rpc.events.*;
     import mx.controls.ToolTip;
     //Trigger the HTTPService to fetch data from the back-end
     public function fetchData():void
          myServ.send();
     public function faultHandler(event:FaultEvent):void
          Alert.show(event.fault.message);
]]>
</mx:Script>
<mx:LineChart id="myChart" width="100%" height="100%" showDataTips="true" dataProvider="{myServ.lastResult.tasks.task}">
     <mx:horizontalAxis>
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     </mx:horizontalAxis>
     <mx:verticalAxis>
          <mx:LinearAxis title="My Data Values"/>
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     <mx:horizontalAxisRenderers>
          <mx:AxisRenderer axis="{myHorzAxis}" labelRotation="45"/>
     </mx:horizontalAxisRenderers>
     <mx:series>
          <mx:LineSeries id="myLineSeries1" xField="name" yField="Value">
          </mx:LineSeries>
     </mx:series>
</mx:LineChart>
</mx:Application>
TempChartData.XML
<?xml version="1.0" encoding="utf-8"?>
<tasks usl="25" lsl="-75">
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    </task>
    <task name="2">
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    <task name="3">
        <Value>-100</Value>
    </task>
    <task name="4">
        <Value>0</Value>
    </task>
    <task name="5">
        <Value>-74</Value>
</task>
    <task name="6">
    <Value>0</Value>
    </task>
    <task name="7">
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    </task>
</tasks>

Please do not post VIs with infinite loops (at least without informing us that they work that way)! The loop should have a stop button on the front panel wired to the stop terminal in the loop. If you use the Abort button to stop the VI, the file never gets closed.
A long time Forum participant has said that: "Using the Abort button to stop a VI is like using a tree to stop a car. It works but may have unintended consequences!"
To get the format you want after reading you need to convert the first column in the spreadsheet file from a date-time string to a numeric which can be interpretted by the graph as a timestamp. With the format you have chosen for the file it is somewhat complicated. Spend some time reading the detailed help for the timestamp and string format functions.
In the VI attached the file is read as string. The first column is separated into 7 numerical values to create a date-time record (cluster) which is then converted to a timestamp and then to DBL. The second column is converted to an array of DBL. The arrays are bundled and connected to an XY graph. The graph X-Axis is formatted as Absolute Time, AM/PM, HH:MMS. You can add the fractional seconds if you want but the scale starts to get crowded.
Also, the error out wires from the property nodes used to initialize the graphs should be wired to the loop to assure that they execute first.
Lynn
Attachments:
test_3.2.vi ‏26 KB

Not enough memory to complete operation

I've looked through the forums for the "not enough memory to complete operation" error and despite following the advice I found, the error still occurs.
I'm using LabVIEW 2012 to try and continuously monitor our system, recording temperature, power, etc vs time (values obtained from USB-6008 DAQ). The data being saved to file, is done every 60 seconds using a small array (no problems here). The typical run/time memory allocation to LabVIEW is about 180MB (4GB RAM on computer).
The issue I feel is related to our wish to display this data on graphs for extended periods of time. The current iteration of the code works as follows.
1) we have 2 XY graphs with 2 plots each.
2) for each plot, I am initializing clusters of 2 arrays of 100,000 (XY pairs) which are wired to shift registers. I know this is larger than can be displayed on a graph but I am currently more concerned with reducing the number of data copies.
3) Every 10th data point is added into the arrays using an In Place Element Unbundle/Bundle along with a "Replace Array Subset". This means there are approximatly 8640 points per day. (A single day is the shortest time span typically viewed)
4) For two plots on an XY graph, two clusters are combined in an array (using Build Array). I think this is my problem right here. Since everytime I update the graphs Labview has to allocate memory for the 4 XY plots. ( Am I correct here?)
Decimating the data further when looking over multiple days will reduce the amount written to the plots. However this operation creates data copies. Is it worthwhile in this case?
Instead of initializing 4 clusters (1 for each plot) and combining into arrays later, would it be better to initialize Array of cluster of arrays (2 plots per graph) and update the data by "index / unbundle / replace array subset / bundle replace array subset" series of operations?
Solved!
Go to Solution.

Hooovahh wrote:
But what I think is more important is your middle loop is unbounded in size for its arrays. Memory will continue to grow until it crashes. You removed the write VI but I'm guessing you are essentially overwritting the old file with all the same data but with 1 extra data point. Why not just write that one extra data point by appending to the existing file? Look at the Write To Spreadsheet which shows how to append to file (it is an optional input).
If you'll notice the section where I comment that the save VI is deleted, there is a null array wired to the shift register. While this probably isn't the best practice, the array builds to 60, appended to the text file, and overwritten with the null array. This is to avoid opening/closing the file every second.
The other array there stores power and time for every data point when the sun is up for the day (probably near 50,000 data points). This is done to calculate the days insulation by integration. This array could probably stand some improvement using an initialized array. (i got tunnel vision on the other part of the code and missed this).
In regards to the graphs containing multiple days worth of data to be viewed at any time, yes this is a requirement (the more the better). This is for monitoring a solar array at our University and, once free from bugs, will be linked to a web page using the Web Server. So individuals may view data within the past 1,2, or even 3 weeks. Normally, I would just have a separate VI for viewing data when desired but 24/7 access to view the updated data is a requirement.
Am I correct in that the Build Arrays (just prior to the graphs) makes a data copy of each cluster? Could it be this large data copy that's the cause of the error? My understanding from other posts is that this error is generally linked to non-continuous memory allocation for arrays/clusters.

How do I plot XY-Graph if case is true?

It seems to me that it always has to be a while-/for loop before XY-Graph, I need a Case window instead, is that possible? If, how do i make it work?

The XY graph takes an array of bundled XY values (or vice versa) as input, it does not care how that array has been created or whether it is in this structure or that. I think there must be some basic consept that you are missing, but upload a copy of your VI or a picture of the code and explain what you are trying to achieve, and we'll probably find a solution.
MTO

Help my with XY Graph

Hello.
I need to make a XY graph but i don't know how to connect the graph with the rest of the program.
There should be two column which are imported from two other files. One will be the X values , and the other will be the Y values.
I've tried a lot of different ways to show the plot, but ewerytking is still not working.
So please help me ang i will be grateful.
Attachments:
wan.vi ‏19 KB

Currently, you read your data into an array of strings. For graphing, you need a numeric datatype. WIre an empty 1D DBL (instead of a 1D array of strings) to the type input of "spreadsheet string to array", then bundle the two 1D arrays.
Of course easier would be to use "read from spreadheet file", it will give you numeric datatype directly by default. Since you seem to have a single column instead of a single row in your file, you possibly need to transpose (see the boolean). Attached is a simple example (image), just wire it all up.
Message Edited by altenbach on 01-29-2007 05:35 PM
LabVIEW Champion . Do more with less code and in less time .
Attachments:
XYgraph.png ‏7 KB

Dynamic multiple waveform display

Hi,
I'm a labview beginner. Here I got a quick question. I want to use one waveform graph to display two waveforms (acquired from two channels). As shown in help files, it seems I need use "build array" to bundle the two data streams to one array and output to waveform graph. However, I got an error (error message: ''You have connected an array to its element type?) when I was doing this. Attached is a picture showing my simplified test case. Instead of use data acquired from hardware, in this test file, I use simulated sine waveform.
I knew this could be a very small trick. However, I couldn'd find a way to fix it.
Any help is appreciated.
Attachments:
post1.JPG ‏35 KB

You do not lose a waveform when you use the merge signal function. It is the correct function to use when you work with a dynamic data type. If you converted the dynamic data from the simulate signal to a waveform data type or to a 1D array, then you would use the Build Array function like the help says. To see both signals, just replace the Build Array with the Merge Signals and look at your graph. You don't have to 'guess', you just have to do it and see

What protocol does the NI-DSA THD driver (or any harmonic analyzer driver) use to find and interpolate if necessary, harmonic frequences and corresponding amplitudes?

When using the NI-DSA THD driver to obtain harmonic data, I find that the haromic frequencies found sometimes doesn't come close to the expected harmonic frequency.
For instance, if I use a 20kHz span and 400 lines of resolution I would expect 50Hz bins. So if my fundamental is 500Hz, I would expect to see 6000Hz at the 12th harmonic but the THD driver can be off by up to 150Hz (ie, 6150Hz or 5850Hz).
The output of the harmonic analyzer driver is an array of bundled values that contain x0, dx, and a data value array. Is it safe to say I can use this data to calculate exact harmonic test data (ie,
x0=0, dx=50 so x(10)=harmonic amplitude at 500Hz and x(120)=harmonic amplitude at 6000Hz)?

If it is that bug, the fix is in 3.17.3 which is in [core] now.
My experience is crashes like that are usually hardware instability. Last time it happened to me it was because my RAM. I had to underclock it to make it stable. If the kernel update doesn't help you, you could try running a stress test like Prime95.
http://www.mersenne.org/download/
If your hardware is unstable it will usually crash after only 5-10 minutes. If you can run it for multiple hours that can help rule out hardware.

Curve fit

Hi! I want to ask how I can fit a curve and see this in the graph for the obtained 2d array.
I can obtain a 2d array (x-y) as a result of loop iteration clicking "Next Step" button for 14 times. After that, I want to fit a curve for this 2d array as a function of y=f(x).
Also, I want to see the formula, and also function coefficients for this curve.
I have tried a curve fitting as can be seen from the attached picture. However, it always failed. I can not obtain purely x-y curve (y=f(x)). Also, I have attached the sample VI. Could anyone help me ? I'm looking forward to hearing from you.
Solved!
Go to Solution.
Attachments:
sample_the_latest_one.vi ‏182 KB
blockdiagram.JPG ‏51 KB

Could you attach a typical data file? Thanks!
Even better, create an indicator on the 2D array leading to the second loop. Run the VI and start fitting so the indicator contains 2D data. Now make the new indicator a constant with typical data (right-click terminal...change to constant). Now save and attach the VI.
mechen wrote:
I attached the second while loop to use its stop button. I defined its stop button as a "Curve Fitting" button as can be seen from the front panel.
Why not make it a state machine with a single loop? Your data is already in shift registers, so it would be available in the main loop. All you need is another state. The way you program it, you cannot easily go back to reading new data without additional code. Your fitting loop still needs a small wait or an event structure. Fitting needs to be done only of one of the inputs changes and not millions of times per second. You also don't need to wire all inputs, only the ones you want different from the defaults.
Why do you have two instances of the same 2D array diagram constant. This makes the code unmaintainable, because identical changes would need to be done in two different places if you need to modify things in the future.
mechen wrote:
My question is how I can obtain a graph for 2d array.
The x-axis will be the first column of the 2d array. The y-axis will be the second column of the 2d array.
If x is not spaced equally, you need an xy graph. Simply extract the two columns using "index array", then bundle them into an xy graph. Check the shipping examples.
LabVIEW Champion . Do more with less code and in less time .

Nested IPE (In Place Element) usage when accessing Cluster/Array data via DVR

I am sharing data across several VIs and loops via a DVR, and accessing the data via a DVR IPE. The data is a cluster of arrays. The diagram below (VI attached) illustrates the structures invloved, but not the structure of the application.
(The diagram above does not include initialization of the arrays, as it is intended only to illustrate the Cluster1 data type. Array lengths could be 100.)
The DVR (DVR1) is passed to multiple VIs of the application at startup.
Each VI executes loops that either read or write particular elements of each array (fArray1 or fArray2).
I believe the DVR IPE (B1-DVR) provides blocking so that only one task can modify the data (Cluster1) at any time.
Case 1 illustrates how I currently WRITE to array elements. The outer IPE (block B1) is rolled into a VI (not shown) that takes DVR1, Index, and Value as inputs.
Cases 2 - 4 illustrate 3 additional methods that remove one or both of the inner IPEs (B2-Cluster and B3-Array).
Case 2: IPE B3 (Array Index/Replace Elements) is replaced with a non-IPE 'Replace Array Subset'.'
Case 3: IPE B2 (Unbundle / Bundle Elemnts)' is replaced with a non-IPE cluster 'Unbundle'/'Bundle'.
Case 4: removes both B2 and B3.
I implemented case 1 a long time ago. When I had to do the same thing again recently, I did case 4. When I stumbled across my earlier implementation, I was a bit suprised
Which of the 4 cases should take the least time (or resources) to execute? I think case 4 has as few array allocations as any of the other 3.
The attached image did not capture the Buffer Allocation marks, so I marked the ones that differed with a red "B".
I am only interested in differences in how the arrays are handled, so I see no signioficant differences.
Is this one of those cases where LV doesn't need my help?
Incidently, I recently wrote a small app with shared data and decided to try FGVs to share array data. For small arrays, 10^7 iterations, and an FGV based array-element read followed by a element write, the FGV was faster. 1.2us per read/write for FGV vs 3us per r/w for an DVR/IPE based read/write (like above).
Peter
LV 2011 SP1, Windows 7 64-Bit
Attachments:
IPE.vi ‏9 KB

Option 1 is a definite no and as far as I know it has been NI's explicit intention to steer clear from it. I believe there's an idea in the IE which asks for this.
I agree that option 2 makes sense, but I don't think it should be something the user specifies. Either LV can detect it automatically or it can't, but I doubt NI would let you have an option which creates the possibility for this kind of bug.
I'm not sure, but the mark as modifier option on the IPES might be the option you're looking for. I know that it exists and I know very roughly what it does, but the documentation for it is very limited and I never actually played around with it, as usually I don't need these kinds of optimizations.
You may well be right that a new option on the IPES is desirable and you should probably add it to the idea exchange.
As for NIWeek, I'm not going this year, so I have no idea what kinds of sessions are around, but it's a great place to find people who know what they're talking about and ask them about it directly. Certain people in LV R&D would probably be ideal for this and if you ask relevant people, you might even get their names. I'm sure buying them a beer would also help to loosen their tounges. If you ask me, this type of interaction is the main value of the conference, not the sessions themselves.
Try to take over the world!

A sparse image or sparse bundle question in relation to a NAS

Hi all,
I want to create a sparse image or bundle on my Synology DS713+ NAS to store my iPhoto and Aperture libraries.
The reason for a sparse image or bundle lies in the fact that both iPhoto and Aperture very much like a solid Mac Journal formatted drive to operate on.
Because I use an iMac and a MacBookPro I want these libraries available for both computers, and while they reside on a NAS they are 'automatically' backed up, and acessible to both computers.
I've tried storing the iPhoto library on the NAS directly (not Mac formatted but some Linux format, nót FAT32 anyway), but this was performing very poor (copying the library took hours and hours), and I've read on many NAS and Synology forums that this is not the way to go. The best solution I've read from these forums is to create a Sparse Image or Bundle on the NAS to benefit fully form an iPhoto or Aperture Library.
Now I have created a Sparse Image, and mounted it, and moving (copying) an iPhoto Library to it is done in a snap (amazing).
But having the Sparse Image mounted on my iMac, I cannot acess it on my MacBookPro unless I first umount it on the iMac, and then mount it on the MacBook.
Is there a way that such a Sparse Image can be mounted on more than one computer at the same time. In my case, mounted on both the iMac and the MacBook?
Or must it specifically be a Sparse Bundle to accomplish this, or maybe some Terminal wizzardry to get this done?

I'm a little confused here, but what you did answer did help quite a bit. Thanks for that. Anyway, I'm having problems adding to the array. It keeps telling me 'cannot find symbol - method add (double). I'm assuming that this method should be defined in the AuditRecord class, which has been given to me but there seems to exist no method in that class called 'add'. I suppose I could make one, but my professor said that we shouldn't be modifying the AuditRecord class at all, which leads me to believe I'm on the wrong track again. Anyway, here's my updated code in the hopes that it's a simple mistake that I'm making once again:
public class AuditTrail
    private ArrayList<AuditRecord> auditTrail;
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public AuditTrail()
   auditTrail = new ArrayList<AuditRecord>();
* Add a record
public boolean add(double amount)
       if (amount > 0)
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       AuditRecord auditTrail = new AuditRecord(amount);
       //auditTrail.AuditRecord(amount);
       auditTrail.add(amount);
       System.out.println("Amount of "+amount+" added.");
       return true;// similar behavior to a collection
    else
        System.out.println("Invalid deposit amount.");
        return false;
}

How to highlight a specific element of an array

I'm having some trouble selecting which element in an array has key focus. I want to be able to selectively highlight individual elements in an array of strings and set the key focus so that the user can immediately enter the text into that specific element.
I have been able to get "selection.start" and "selection.end" to work, but when I get a reference to "array element" it always returns a reference to the last element manually clicked. This way, I can only programatically highlight different elements by manually clicking on them, which somewhat defeats the purpose.
Does anyone know if this is possible, or if I need to move to tables or something else in order to give me this functionality?
I'm using LV 6.1
on W2k.
Thanks
Shane.
Using LV 6.1 and 8.2.1 on W2k (SP4) and WXP (SP2)

I had the problem that I would like to highlight more than one cell in a 2d array.
multicolumn listbox is very slow working with large data volumes so I had to use a 2d array instead, but then I lose the possibility to highlight.
The solution I used was to bundle a LAD and control an put this in the array, takes a bit more coding but works fine.
Attachments:
2d array with marker.vi ‏23 KB

Arrays to bundles?

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