Problem: Fitting Lev-Mar with Error Function

Hi everyone,
I have very little experience with LabVIEW and I'm trying for the first time to do some NonLinear Curve fit for some data I have.
I've searched in forums for almost a day and couldn't find what I need. The problems are:
1) I need to fit a function of the following type: P = Po/2 - Po/2*erf(sqrt(2)*(x-xo)/w) , where Po, xo and w are my parameters.
But in my error2.vi I cannot link my y=sqrt(2)*(x-xo)/w  variable of the erf function to the input, because the erf.vi does not accept 1D array as input and doesn't give that as output as well. The output thing is another problem, since the input of F(x,a) needs to be a 1D array.
2) I read about the Lev-Mar NonLinear CurveFit VI and I think I got what needs to be done. However, a I was having problems in wiring my Static VI Reference to the F(x,a) input in the Lev-Mar VI and it didn't give me a broken wire only when I made de Reference a "Strictly Typed VI Reference". What does that mean? Why did it only work with that?
I know these are some pretty basic doubts, but I've been trying to understand it for quite some time and couldn't get this done.
Thanks.
PS* The fitting function (subvi) is the error2.vi file.
Solved!
Go to Solution.
Attachments:
error2.vi ‏13 KB
FittingGaussianKnife.vi ‏15 KB

Try this. Seem to work  just fine (LabVIEW 2013).
(don't try to graph the best parameters, graph the best fit output!)
LabVIEW Champion . Do more with less code and in less time .
Attachments:
FittingGaussianKnife_MODCA.vi ‏17 KB
error2_MODCA.vi ‏14 KB
erfit.png ‏40 KB

Similar Messages

  • Process chains problems : Working every day with error (red)

    Hi All,
    I have a next question, about process chains problem.
    When I start my process chains immediate, then working without errors,  but I want this process chains work every day and chainged properties, selected date/time and periodicaly (every day) but now it work with error.
    How to I find problems? What are yours offers?
    p.s. I see logs, but every day have diffence between errors.
    Regards,
    Mahir M. Quluzade

    HI,
    just check the time which you have given is OK or is overlappintg with some other job which is locking your table in process chain
    or is colliding with attribute change run
    or it fails because of lack of background processes.
    There could be numerious reasons and you need to analyze the log for this.
    But as you said the job is failing everday for different reasons..try to find the most common errors and try to remove it or mention that here.
    Thanks
    Ajeet

  • ABAP program is terminated with error Function ROLLBACK on connection R/3

    Hi,
    We are reading a DB table A and matching with table B and placing into a internal table and further looping at the internal table.
    Table A has 3- 5 million records
    Table B has 2-4 million records
    When the program run in batch or dialog process, it stops without apparently reason, it don not trace any log in ST22 transaction. When we trace it in SM21 trace the following log:
    22:18:33 BTC  014 100                BZ  Y Unexpected return value 1 when calling up DbSlR
    22:18:33 BTC  014 100                BY  J Function ROLLBACK on connection R/3 failed
    22:18:33 BTC  014 100                R3  9 Error in DB rollback/SyFlush, return code 016384
    22:18:33 BTC  014 100                Q0  2 Stop Workproc14, PID 729286
    22:18:33 BTC  014 100                F3  T Invalid object name for TemSe object: " "
    22:18:33 BTC  014 100                EC  F Failed to create log for job BIDTPR_291659_1 22085900%_IMMEDIATE %NEWSTEP/
    22:18:33 BTC  014 100                F2  0 Calling program reports invalid handle for TemSe object (magic==X'NULL-ptr'
    22:18:33 BTC  014 100                R4  7 Delete session 001 after error 023
    The tables and ABAP program are in a BW system.
    Any idea what would be the cause. I found  a similar problem in the forum but no solution provided there..
    Regards
    Rob

    Hi Rob,
    Please check the entries in the work process trace file from this time (dev_wp14 from the work directory)
    Error in DB rollback/SyFlush, return code 016384
    usually has a preceding entry in the wp log of
    SHO: Could not allocate SHO segment of ..... bytes (rc=1)
    Usually this is a result of a SELECT statement that returns a very large result set is executed.             
    While the result set is fetched the ABAP heap is exhausted. Since no             
    more memory is available the ABAP engine abruptly cancels the execution          
    and begins error handling. The database interface rejects to execute a           
    ROLLBACK statement while the SELECT statement is still active. As the            
    rollback fails the task handler restarts the SAP work process and no             
    ABAP short dump or job log entries can be written.                                                                               
    The rejected ROLLBACK is a direct result of the lack of ABAP heap memory         
    and does not represent an error in itself.                                                                               
    The solution here is to increase the memory areas "extended memory" and          
    / or "heap". Please check/adjust your SAP memory settings!
    As mentioned, Similar issues have been resolved with the note #741864.                     
    The key is that the abap/shared_object_size_MB is too small for the          
    system and the operation performed, please increase this to 100MB to         
    start from the default of 20MB and then increase further if the dump         
    persists as more maybe needed of course. There is no problem increasing      
    this parameter since you have a 64bit system and SAP kernel.                                                                               
    Similar issues have been resolved with the note #741864 and note #986790     
    along with the increase in abap/shared_object_size_MB. These notes may       
    not be necessary just the increase but this issue frequently occurs in       
    these areas so perhaps they can help.                                        
    Hope this helps,
    Paul

  • Problems opening Word docs with form function

    Does anyone know how to open a Word doc & keep the forms function? I have to fill out quarterly reports. When I open this type of Word doc, Pages eliminates the checkboxes and text boxes. A pain point, but Word doc is still usable.

    Hi,
    Since the issue only occurs to Word for Mac, I'm not familiar with the mechanism how it opens a file, we mainly supports Office for Windows in this forum. Please post the question in Office for Mac forum for further assistance:
    http://answers.microsoft.com/en-us/mac
    The reason why we recommend posting appropriately is you will get the most qualified pool of respondents, and other partners who read the forums regularly can either share their knowledge or learn from your interaction with us. Thank you for your understanding.
    Regards,
    Melon Chen
    TechNet Community Support
    It's recommended to download and install
    Configuration Analyzer Tool (OffCAT), which is developed by Microsoft Support teams. Once the tool is installed, you can run it at any time to scan for hundreds of known issues in Office
    programs. Please remember to mark the replies as answers if they help, and unmark the answers if they provide no help. If you have feedback for TechNet Support, contact
    [email protected]

  • I've had Itunes since 2009.  Purchased a new computer and attempted to install Itunes with running Windows 8 and encountered a problem.  Itunes stopped with error 2324. Having problems trying to reinstall Itunes.  Help please.

    I've been and ITunes customer since 2009.  I have a ipod classic with close to 9,000 songs.  I recently purchased a new laptop and attempted to download the latest ITunes version 12.0 to my laptop.  I'm running with Windows 8.  During the download, ITunes stops and gives error code 2324.  Can't reinstall ITunes. ITunes doesn't work.  Please help.

    Hi chenalej924,
    We've an article (linked below) that details a number of steps which can help get iTunes successfully installed on your computer.
    Issues installing iTunes for Windows
    http://support.apple.com/en-us/HT201668
    Regards,
    Allen

  • Curve Fit of ODE, should I use Lev-Mar or Constrained Nonlinear Optimization?

    I wanna do a curve fitting of differential equations, following is the equations:
    dx/dt = u*x-a*x
    ds/dt = b*u*x+c*x
    dp/dt = d*u*x+e*x+f*p
    and u = um*s/(km+s+s^2/ki)
    I've tried "nonlinear curve fit( Lev-Mar)", but I met difficulties when writing the f(x,a) of Lev-Mar.
    Then I tried "Constrained Nonlinear Optimization", I found that the example "Estimate Nonlinear Spring Constant.vi"
    in the "labview\examples\math\curvefit.llb" was similar to the fitting I tried to do, but there was only one parameter
    need to estimate in this example,but what I need is to estimate 3 parameters.
    However,I modified the example to my equations, it failed again.
    How can I achieve this? is it possible to do this fit only using Labview VIs or need Matlab Script Node?
    Any help will be appreciated.

    I forgot to mention that in the equations above,  a,b,c,d,e,f is constant,
    and the data of x,s,p corresponding with the data of time is already known,
    and which parameters I wanna identify is um,km,and ki
    帖子被myafu在12-22-2006 01:33 AM时编辑过了

  • Problems with planning function in Web Application Designer in 2004s

    Hi All,
    I have a problem in WAD 2004s with planning function. I created a web template that includes a query. It runs on the enterprise portal, and I can edit this query. The problem is: I don't know how to save this edited query, because when I use the button with function save, the new value doesn't appear in the relevant info cube.
    Anybody can help me how to save the new values to the info cube?
    Thanks in advance
    Dezso Toth

    I don't know if you ever resolved this, but you may just ned to change a setting on your query properties.  When data is entered into planning layouts and saved, that data is put into a "yellow" request in the underlying infocube. 
    Until the necessary volume of data is posted which causes this to change to "green", it remains yellow.  Note that this request could also be changed to green several ways.  i.e. manually, by flipping the "real-time infocube behavior" switch, etc. 
    Anyway, as long as it "yellow" your query, by default will not consider it, unless you change it's properties to tell it to consider "yellow" requests.  This can be done via RSRT and pressing the "properties" button.  Choose request status "2" and your problem should be solved

  • Lev-Mar template missing

    I am trying to fit A*sin(w*t+phi) to some noisy data (amplitude, frequency, and phase are all to be detrmined from the matched sine). When I looked at the Lev-Mar fitting VIs I could not locate the template for the LM model function and gradient VI template mentioned in the Help file. labview\vi.lib\gmath\opti.llb\numerical is empty. (Help says this template should be there). The figure in the help file shows a cluster called Output Control as an input to the VI, but does not specify the elements of the control. I also could not find a way to put the formula into the String Formula version. Is there a listing of the available functions and syntax? The help did not seem to lead me to it.
    LV8.0.1 on Mac OS X
    Maybe it is just too late on Friday afternoon.
    Lynn

    Sarah, Christian,
    I had looked at that link and several others. I was hoping to find some reference where someone had made some practical suggestions reagrding optimizing the initial guesses, or at least some clues as to how to go about it.
    My data has a frequency range of about 2.5:1 so I was hoping I could just set the initial guess at the middle of the range. In my testing an initial guess 20% above or below the actual frequency resultis in erroneous values about 80-90% of runs with noise at 10% of signal amplitude which is better than the real data. With initial amplitude and phase equal to the data parameters and initial frequency guess at 1.2 times the actual I recorded two runs with the fit frequency at 99.9%. Eight others produced: 160%, 180%, 210%, 160%, 160%, 130%, 60%, and 160%. With the initial frequency at 80%, the results were somewhat worse.
    My suspicion is that because the partial derivatives of the model equation are also sines and cosines, the algorithm tends to find some kind of local minimum and converges to that even though it is a really poor fit.
    Here is my modified Lev-mar VI and the simple sine model VI (LV8). The default values are fairly typical of the data sets we will be getting.
    Thanks for the help.
    Lynn
    Attachments:
    Nonlinear Fit Lev-Mar.Berry.vi ‏41 KB
    simple sine model.vi ‏21 KB

  • Lorentz fit of a curve with Lev-Mar

    Hello everybody! I am trying to set of data to a Lorentz curve to calculate a Q value (resonance.) I found a program on a thread from this forum that appears to work with the sample data set from the thread. However, when I try to run the program using my data set with known fitted coefficients as the initial guesses, we get an error in the Lev-Mar sub-VI -- something like “the input matrix is singular”. There’s a screenshot of my data in in the attached zip folder, as well as the text file containing my data.
    My data curves down (reaching a minimum) instead of up, as in the sample data set, but it seems like that should be accounted for by the different initial guesses. I am thinking that something else is going on; hopefully it is something simple that I am just missing. Any help y'all can provide would be greatly appreciated!
    Thank you!
    Attachments:
    Lorentz Fit.zip ‏1992 KB

    Hello Lynn,
    Yes, there are quite a few potential peaks in that data set. The peak you identified was the one that we are trying to fit (The peak should be trimmed by the cursors.) We used origin to fit that same peak in order to get the initial guesses for the coefficients in the screenshot. When it runs, we get the error message: "Error -20041 occured at NI_Gmath.lvlib: Nonlinear Curve Fit LM.vi:2 Possible reason(s): Analysis: The system of equations cannot be solved because the input matrix is singular." 
    Thanks!
    -Garrison

  • Error thread java : problem with the function "resume 0x***"  (forum sun)

    One problem with the function of jdb occured when I tried to use it to
    pilot the processor with differents threads. In fact, I use a simple example with 2 threads.
    I stop the two threads with two breakpoint, and I want to resume one or the other (with the function "resume 0x****"), the one wich I resumed stop again on the breackpoint and I decide again to resume one or the other. All of that to obtain a tree of execution.
    I give you the code of the class and the code of jdb.
    CLASS: (it's just a object Room with a variable degre that I increment and decrement with two threads increase and decrease)
    public class Test{
         public static void main(String[] args){
              Room r = new Room();
              decrease de = new decrease(r);
              increase in = new increase(r);
              de.start();
              in.start();
    class Room {
         private volatile int degre=20;
         public void more(){
         degre += 4;
         public void less(){      
         degre -= 3;
    class decrease extends Thread{
    private Room room;
    public decrease(Room r){
              room =r;
    public void run(){
    try{ 
         while (!interrupted()){ 
              room.less();
    catch(InterruptedException e) {}
    class increase extends Thread{
    private Room room;
    public increase(Room r){
         room =r;
    public void run(){ 
         try{ 
              while (!interrupted()){
                   room.more();
    catch(InterruptedException e) {}
    JDB:
    Initializing jdb ...
    stop at Test:7Deferring breakpoint Test:7.
    It will be set after the class is loaded.
    runrun Test
    Set uncaught java.lang.Throwable
    Set deferred uncaught java.lang.Throwable
    >
    VM Started: Set deferred breakpoint Test:7
    Breakpoint hit: "thread=main", Test.main(), line=7 bci=30
    7 in.start();
    main[1] stop at room:16
    Set breakpoint room:16
    main[1] stop at room:20
    Set breakpoint room:20
    main[1] resume
    All threads resumed.
    >
    Breakpoint hit: "thread=Thread-0", room.less(), line=20 bci=0
    20 degre -= 3;
    Thread-0[1] threads
    Group system:
    (java.lang.ref.Reference$ReferenceHandler)0x10d Reference Handler cond. waiting
    (java.lang.ref.Finalizer$FinalizerThread)0x10c Finalizer cond. waiting
    (java.lang.Thread)0x10b Signal Dispatcher running
    Group main:
    (decrease)0x146 Thread-0 running (at breakpoint)
    (increase)0x147 Thread-1 running (at breakpoint)
    (java.lang.Thread)0x148 DestroyJavaVM running
    Thread-0[1] resume 0x147
    Thread-0[1]
    Breakpoint hit: "thread=Thread-1", room.more(), line=16 bci=0
    16 degre += 4;
    Thread-1[1] resume 0x147
    Thread-1[1]
    Breakpoint hit: "thread=Thread-1", room.more(), line=16 bci=0
    16 degre += 4;
    Thread-1[1] print degre
    degre = 24
    Thread-1[1] resume 0x146 //It's here the problem, thread 0x146 have to stop on the //next breakpoint of decrease but nothing happen
    Thread-1[1] resume 0x147
    Thread-1[1]
    Breakpoint hit: "thread=Thread-1", room.more(), line=16 bci=0
    16 degre += 4;
    Thread-1[1] clear
    Breakpoints set:
    breakpoint Test:7
    breakpoint room:16
    breakpoint room:20
    PS: I tried many other examples with other class and other kind of breakpoints, but, in any cases, on thread doesn't manage to resume. When I try with general resume (no specification of the thread), It works but it isn't interresting for me because I want to decide wich thread continue his execution.

    Hi,
    I have read the FAQ of the JMF.
    The problem was the jar files of the JMF were not in the JRE\BIN\EXT
    folder of the Java runtime!
    now it works!
    thanks
    Reg

  • A confusing lev-mar error

    I am trying to fit a Lorentzian to some acquired data using the lev-mar function, and it returns the error "wrong model equation". I know for a fact that the data has a lorentzian shape because I wrote a little vi to fit it manually using the exact same equation. Does anyone have a suggestion as to what to do next, or at least what the "wrong model equation" error really means? Thank you.
    JPC

    The error refers to a syntax issue with the "model description" input.
    This input is a cluster of three strings: model, which is the actual equation (Ex: a+b*x+c*x^2); paramters, which are the solvable variables (a, b, & c in the previous ex.) inputted as an array of strings; and the independent variable (x).
    All 3 parts of the model must match exactly (e.g. you can't have 3 variables in the model and 1 in the parameters, and if you designate x as the independent variable, there must be an x in the model equation).
    Additionally, the model equation follows standard LabVIEW formula node syntax, except there are no input variables designated ("y=x+1" won't work but "x+1" will) and you don't need a semi-colon terminator.
    Let me know how it goes,
    ~j5
    2006 Ultimate LabVIEW G-eek.

  • Curvefit of the reflectivi​ty with Lev-Mar

    Hello,
    I am a beginner with Labview and I need your help, I recuper the data of the reflectivity from the spectrometer (3648 points) and I am going to make the fitting to extract information about the thickness and refractive indices n and k (k in the general case it will be zero because the materials used are oxides and I work in the visible range.
    I want to use the model of Lev-Mar but I have the problem with the model, i have used the formula node to write the eqaution of the reflectivity, and currently I am block.
    Data.txt
    column1 = Lambda
    column 2 : Reflectivity
    the substrate is Pyrex  ; n= 1,47
    the thin film is Ti-Nb, the index is like that of the titane(Antase) : ñ = 2,561 + i2,488
    Thank you very much.
    Nb: i know my english is so bad
    Attachments:
    fit1.png ‏36 KB
    fit2.png ‏30 KB
    Data.txt ‏51 KB

    Thank you very much Lynn,
    I did what you told me to do and it works a better,
    I would like to know if you can help me, I have the values of the reflectivity R as a function of the wavelength (lambda) but the indices " n "  and " k " are also a function of lambda.
    R = (n,k,d,lambda )   and  the dispersion equation n(lambda) and k(lambda)
    With the curvefit Lev-Mar is possible to define these parameter ? if you have ideas that will be cool

  • Please help on this Lev-Mar problem

    Hi,
    I have two acquisition data sources that need
    to be fitted. Then the fitted parameters are
    passed along with data for further processing.
    As the data is heardware generated, I made a
    similar 'signal generator' to present very closely
    the problem.
    ===Please see the attached vi file===
    As you can see, these two Lev-Mar's function
    / derivatives are obviously different. We can edit
    the fuction / derivative node. But the problem
    is that when one is edited, the other changes too.
    Anyways, we can NOT have two different functions.
    My question is: How to have two different function
    / Deveritives here?
    By the way, how to replace the MatLab box into
    function node in my attached example?
    I can 'wire' the out
    put to next if it's a
    function node. It says the type of variables are
    different (output is a real instead of array).
    Attachments:
    Lev-Mar-Question2.vi ‏99 KB

    You have a few options for multiple function/derivatives.
    1. If you can express the model functions using the formula string syntax, then you might consider using the "Levenberg Marquardt.vi". Unfortunately the Levenberg-Marquardt.vi does not allow the specification of the derivative of the model function and always uses numerical derivatives. It is also somewhat slower than the "Nonlinear Lev-Mar Fit.vi".
    2. You could also save a copy of the "Nonlinear Lev-Mar Fit.vi" using a different name, and also the "Lev-Mar ABX.vi" and "Target Fnc & Deriv Nonlin.vi" with different names. Then you would have a different set of VIs to implement the curve fitting on two different models. This is ugly, but would work.
    3. You could modify the "Nonlinear Lev-Mar
    Fit.vi", "Lev-Mar ABX.vi", and "Target Fnc & Deriv Nonlin.vi" to accept/pass VI references. The "Target Fnc & Deriv Nonlin.vi" would then perform a call by reference to a VI that you wrote implementing the current model function.
    To replace the Matlab script node place the formula node inside a for-loop. The for-loop will auto-index the x and t arrays, and auto-build the y-array.

  • Backups failing with error 19: the backup disk could not be resolved, or there was a problem mounting it

    Hello all,
    Doubt this issue relates to a recent and ugly issue but sharing anyways (resolved thanks to a user here: LaPastenague)
    Time Capsule won't backup if Modem (Motorola SB6121) attached
    This was on Feb 10th resolved. Few days later I upgraded to Yosemite.  Backups were working fine since.  
    Yesterday I happen to notice my last backup was 5 days ago.  I looked in the console logs and saw:
    2/25/15 3:55:06.127 PM com.apple.backupd[2777]: Attempting to mount network destination URL: afp://Paul;AUTH=SRP@Time%20Capsule._afpovertcp._tcp.local./Data
    2/25/15 3:55:17.778 PM com.apple.backupd[2777]: NAConnectToServerSync failed with error: 2 (No such file or directory) for url: afp://Paul;AUTH=SRP@Time%20Capsule._afpovertcp._tcp.local./Data
    2/25/15 3:55:17.792 PM com.apple.backupd[2777]: Backup failed with error 19: The backup disk could not be resolved, or there was a problem mounting it.
    2/25/15 3:57:18.808 PM com.apple.prefs.backup.remoteservice[2021]: Attempt to use XPC with a MachService that has HideUntilCheckIn set. This will result in unpredictable behavior: com.apple.backupd.status.xpc
    I called Apple.  Their front line was clueless. He suggested resetting the TC (latest "tower" model btw") which then a backup kicked off YEAH
    But the next hour it failed
    Called Apple again, this time to Sr Advisor.  He suggested factory reset of the TC and set up again.  Also first backup worked then rest failed
    Third call to Apple useless also.  He was asking questions I didn't feel relevant.  He also was asking me to reset the TC which I told him was done 2 hours prior. He asked me to reboot which I could NOT at that time.
    I begged him to collect data to submit to engineering, which will take days to get a reply.
    So I thought I would throw this out to the community....
    TC Is NEW (replaced from last issue).  Mac is 8 months old (iMac 27"), Os is Yosemite,  TC also new (latest model)
    Thanks...

    Yosemite is problematic on two fronts.. Networking and Time Machine.. so the combo of doing both with a Time Capsule is like bugs on bugs.
    Here is my standard list.. but your problem maybe difficult to resolve.. and my suggestion is simple.. until Apple get their act together and fix TM.. buy Carbon Copy Cloner and use that for your backup. It is solid and reliable.. even better if you use USB drive plugged into the computer and do a bootable clone.. because then you have a backup that is able to be tested for full functionality 2min after the end of the backup.
    This also starts from a factory reset.. but the reason for it is to change the configuration which is much more easily handled with factory reset to begin.. the instructions are there.. because this is my standard reply.. this is not uncommon!!
    Factory reset universal
    Power off the TC.. ie pull the power cord or power off at the wall.. wait 10sec.. hold in the reset button.. be gentle.. power on again still holding in reset.. and keep holding it in for another 10sec. You may need some help as it is hard to both hold in reset and apply power. It will show success by rapidly blinking the front led. Release the reset.. and wait a couple of min for the TC to reset and come back with factory settings. If the front LED doesn’t blink rapidly you missed it and simply try again. The reset is fairly fragile in these.. press it so you feel it just click and no more.. I have seen people bend the lever or even break it. I use a toothpick as tool.
    N.B. None of your files on the hard disk of the TC are deleted.. this simply clears out the router settings of the TC.
    Setup the TC again.
    ie Start from a factory reset. No files are lost on the hard disk doing this.
    Then redo the setup from the computer with Yosemite.
    1. Use very short names.. NOT APPLE RECOMMENDED names. No spaces and pure alphanumerics.
    eg TCgen5 and TCwifi for basestation and wireless respectively.
    Even better if the issue is more wireless use TC24ghz and TC5ghz with fixed channels as this also seems to help stop the nonsense. But this can be tried in the second round.
    2. Use all passwords that also comply but can be a bit longer. ie 8-20 characters mixed case and numbers.. no non-alphanumerics.
    3. Ensure the TC always takes the same IP address.. you will need to do this on the main router using dhcp reservation.. or a bit more complex setup using static IP in the TC. But this is important.. having IP drift all over the place when Yosemite cannot remember its own name for 5 min after a reboot makes for poor networking. If the TC is main router it will not be an issue.
    4. Check your share name on the computer is not changing.. make sure it also complies with the above.. short no spaces and pure alphanumeric.. but this change will mess up your TM backup.. so be prepared to do a new full backup. Sorry.. keep this one for second round if you want to avoid a new backup.
    5. Mount the TC disk in the computer manually.
    In Finder, Go, Connect to server from the top menu,
    Type in SMB://192.168.0.254 (or whatever the TC ip is which you have now made static. As a router by default it is 10.0.1.1 and I encourage people to stick with that unless you know what you are doing).
    You can use name.. SMB://TCgen5.local where you replace TCgen5 with your TC name.. local is the default domain of the TC and doesn't change.
    However names are not so easy as IP address.. nor as reliable. At least not in Yosemite they aren't. The domain can also be an issue if you are not plugged or wireless directly to the TC.
    6. Make sure IPv6 is set to link-local only in the computer. For example wireless open the network preferences, wireless and advanced / TCP/IP.. and fix the IPv6. to link-local only.
    There is a lot more jiggery pokery you can try but the above is a good start.. if you find it still unreliable.. don't be surprised.
    You might need to do some more work on the Mac itself. eg Reset the PRAM.. has helped some people. Clean install of the OS is also helpful if you upgrade installed.
    Tell us how you go.
    Someone posted a solution.. See this thread.
    Macbook can't find Time Capsule anymore
    Start from the bottom and work up.. What I list here is good network practice changes but I have avoided Yosemites bug heaven.
    This user has had success and a few others as well.
    RáNdÓm GéÉzÁ
    Yosemite has serious DNS bug in the networking application.. here is the lets say more arcane method of fixing it by doing a network transplant from mavericks.
    http://arstechnica.com/apple/2015/01/why-dns-in-os-x-10-10-is-broken-and-what-yo u-can-do-to-fix-it/

  • Varying Lev-Mar init. conditions causes wide change in fit coeficients.

    Hey, I'm trying to use the advanced Lev-Mar fit vi to fit an exponential decay with an offset. I noticed that when I vary the initial condition for the time constant by 5% I get significant changes in my fit coeficient for the same parameter. However, when I multiply my input Y values by 10^4, the fit coeficients are more robust and change little with initial conditions that vary more than 10%. Also, the values now seem to match well with values I obtain when I perform the same fit in the Origin plotting program. Why is this? All my values are in double precision so I don't see how this could be a precision issue.

    The Lev-Mar has a well-known "bug" in the termination condition IF you fail to wire the "standard Deviation Input". In this case, the standard deviation is taken as 1, which is fine except for the case where your y-data is very small (e.g. all in microvolts or nanovolts). In this case, the function is considered converged after one iteration using the initial guesses.
    You have two options:
    (1) (not recommended) Edit the Lev-MAR.vi and make the diagram constant in the bottom center much smaller.
    (2) (RECOMMENDED!) Always wire a "standard deviation input array". In your case, just create an array with equal size as your data, initialized with numbers corresponding to the noise in your data. It does not need to be accurate, you could just take it as e.g. 10E-4 to 10e-6 times your y-range (y-max minus y-min).
    LabVIEW Champion . Do more with less code and in less time .

Maybe you are looking for