Similar Questions

• Variables in the function MathScript ode solver

  Hello

  I'm using LabView for awhile and I started using the text tools more. To solve a system of differential equations, there is this very elegant tool to do this in a MathScript node with the ode solve algorithms (for example, "ode_adams"). As the LabView help said, I've defined a function and registered as a ".m" file. I loaded this function in mathscript and solve differential equations.

  Both and so good, but my problem is that I can not all variables in the function. I can only put numbers in the function but not variables. Unfortunately I need to define the variables outside the function in the MathScript node.

  Does anyone have an idea how to manage the variables in this case?

  I have attatched a picture of the function and test VI (LV2014).

  Greetings

  Global variables to solve this problem:

  Solution:

  

  Greetings

• Simulation loop ODE Solver

  I get error 2324: Labview Simulation Module: the ODE Solver cannot meet the tolerance of errors using the minimum landing size. I've broken down my code and my function of propagation of the signal seems to be the cause. If I multiply things, it works fine. If I do, I get the error. Any ideas?

  Thank you

  Brian

  
  

• Function of memory in the loop control and Simulation - problem of the ODE Solver

  Hello

  I'm correctly using the control loop & simulation to simulate the behavior of what is essentially a shock absorber-spring-mass system. In the process of change in time (dt) is used to integrate an arbitrary value. I use a rack depending on memory to store the time, to calculate the change of time (dt).

  The simulation is quite complex, because of the precision required, not all the ODE solvers can all support. Currently I use the Adams-Moulton method, this works very well for the simulation. However, it cannot detect the change in time, the change is constantly zero. This problem has auto market by using an another ODE Solver, but then the simulation has been messed up instead (even when I listen to the step sizes and tolerances). So I'm pretty confident that Adams-Moulton is one of solver ODE best suited to the problem at hand.

  Is there another way to store the previous hour and use it calculate lag, that the use of the memory function? Everyone knows about these problems before?

  I did a lot of research of error using the probe, but I'm sure that there is a problem with the ODE Solver and memory function. See the image below, showing basic how is calculated the change in time.

  I'm pretty new to LabVIEW, so if there is something else I missed I would be happy to hear it.

  PS! I set the tolerance minimum step of size/relative and absolute for the Adams-Moulton to simulate the behavior of the system properly.

  Problem solved!

  It turns out that the ODE Solver has struggled because of two "table 2D find" used functions. This was created for the interpolation/extrapolation, which caused a problem constantly and the ODE Solver could not resolve correctly, so the functions of memory doesn't work does not correctly or the other.

  By increasing the table manually, I could use closest method instead, with also good results as interpolation.

• Error in setting of simulation in the ODE VI

  Hello

  I use the Gmath library OR where I am going have a "error-2341: Simulation settings: Simulation time ' in the VI.vi ODE. The VI works fine on MAC OS X on Macbook Pro, however giving the error above on the Macbook Air. The operating system both systems is the same, i.e. OS X EL Capitan 10.11.3.

  I am also having the same error when I run the VI on Windows 7 installed as a dual operating system on MACbook Pro.

  Are there any planned hardware problem? Because same code works on the Macbook Pro MAC OS (not on windows 7), but not on Macbook Air.

  Any help is appreciated.

  Concerning

  Hasan

  HB,

  I think that the cluster command may be part of the problem.  The full error message states: "the initial time of the simulation cannot be greater or equal to the last time." The values in the cluster of Simulations settings on the front panel do not violate this condition.

  However, I have created an indicator by popping up on the simulation of the ODE Solver.vi connector pane settings input terminal. When I wire to show that sees the Solver VI, I get last time< initial="">

  Try to replace your control of parameters of Simulation with a created from the entrance of the ODE Solver.

  Lynn

  

• The Solver RK4 VI has a maximum length of scan?

  I have to solve a differential equation in one of my report, and after adding in a new logic (which decides whether or not to include an additional number in the equation), it stops the execute. The Solver, RK4 VI East-23009 error: error in the right-hand side of the equation. Covering over the stream, I've isolated to two eq'ns: dG/dt and dI1/dt, who both have their own VI in the case of ODE solver. I have all converted to a width of 8, precision channels 12 and I think that my newest additions have exceeded the limit digitization of execution of RK4 screws max. inside, I quickly found that I can't really understand what is happening, so I come to you.

  Some good starting parameters:

  in VariableCluster.ctl, set Xa 100 X (t - 1) de.01, I1(t-1) 10, I2(t-1) a.5

  control.CTL constant, the value weight 80, activate auto of Glucose.

  EDIT: to start execution, run solver.vi ODE which is located in the folder of ODE solver.

  In VD.vi VD is set to the value of the constant of VD Mult (hidden) which by default is zero. Later, this value is used as a divider that produces NaN values in f. I have no idea whether it is what you want, but the NaN will keep it forms solve anything.

  I have not dug down beyond that point.

  Lynn

• How can I get a digital WDT which includes all samples, not only that of the current stage of time...?

  See block labeled "digital data" in my attachment for reference. Currently, we can consider that the point of digital data for the current time step (it is removed before the following appears). However, I like it showed all the samples in the table as in the example that appears on this link under "digital waveform control":

  http://zone.NI.com/reference/en-XX/help/371361H-01/lvconcepts/fp_controls_indicators/

  Thanks a lot for your suggestions! I am new to Labview, so I appreciate your help.

  Hey westerman111,

  If you are looking to produce your display includes information of the previous steps of Solver solution, you'll need to buffer the previous data. How to implement this in a loop of Simulation of design by & control uses the Memory.vi under control design Simulation & > Simulation > utilities > Memory.vi. It will allow you to save previous information generated in the simulation for letter simulation environment.

  I've attached an example that should help you get started using the Memory.vi.

  I'd also sure that what you are trying to achieve is suitable for the control loop & Simulation. I know you said that you were new to LabVIEW, so I wanted to make sure that you went to sea in the right direction. Is there a particular reason, why you use the control loop & Loop Simulation instead of a standard time or a forum? The loop control design simulation & is unique in that it calculates the solution of a dynamic system to a no prescribed time and the ODE solver. It also provides tools to interact with the model you solve during execution. However, if you are looking for measurements (instead of the simulation of the dynamic model) and data acquisition I advise to use the standard features of LabVIEW.

  Here are a few useful references for the departure with the two LabVIEW Control Design and Simulation Module.

  Tutorial: Introduction to Simulation (Control Design and Simulation Module)

  http://zone.NI.com/reference/en-XX/help/371894G-01/lvsimhowto/sim_h_gs/

  Getting Started with LabVIEW

  http://digital.NI.com/manuals.nsf/WebSearch/ba2fb433a7940e7a862579d40070cc2c

• Order to internal model with cRIO, synchronization of time loop

  Hello

  I work with control design Simulation & toolkit and I want to implement an internal model control to a real-time target. I want to implement my simulation (as an attachment) to the real target (cRIO-9024 OR cRIO-9112). I removed the transfer function of the process, I broke the line and I added my input/output of the cRIO modules. I put a 1ms, Euler ode solver step size and synchronize the time loop. Unfortunately it does not work properly. The loop decreased the speed a lot and I can't get 1 ms response time and, finally, a good answer for my system. This means that I can not 1ms response for loop? What is the problem of the computer, windows or hardware real-time or software? Simple or I did something wrong? All the advice you will enjoy.

  Kind regards

  Kamil

  
  

• Average values for separate sets of data graph XY multiplot

  Hello

  I'm using Labview 2010 and I'm a bit of a novice, unfortunately.

  So I am currently trying to get average values of the three plots I have on a multiplot XY Chart. I thought the best way to achieve this would be to use the express VI of statistics, but when I try to wire the data I need for this I can get statistics for a set of data and not the other two.

  I don't know how the separately on data sets, as it is not a table.

  If anyone can help me, it would be much appreciated. Sorry for the probable simplicity of the question.

  (The program is basically an ODE Solver, which then displays pressure at different places in a bioreactor).

  In the small LOOP where you have data of y for each parcel in the form of a 1 d table, add a "mean.vi" in the math palette: statistics. AutoIndex the output on the edge of the loop to get a table 1 d containing three ways.

  (In addition, a lot of your code could be considerably simplfified. You can [i] connect directly to the structure of the case and a case of '0' and the other, by default. Better would simply initialize the shift, no means required register. Index table is resizable, so you don't need to a single instance on the lower right corner. Wouldn't be easier to just get the latest column and it wire back the entrance inside the structure cases via the feedback node? No need to "subset of table to replace").

  You have forgotten to attach a Subvi, so we can't really test.

  EDH is a quick project:

• Control and simulation and data acquisition

  Hello

  I am applying to motor control in Labview. I'm sampling speed from DC engine in real time through an acquisition of data. (my sampling time is 1000 samples per second)

  Then wrap speed as input to a Simulation (simulation and design of the order) and inside the loop simulation, I have a PID controller. The PID has the actual speed of the engine for the acquisition of data and the engine reference speed as input.

  Reference engine speed comes from the generator of signals (control design and simulation-Simulation) and is a waveform.

  My step in the engine size is 1000.

  I am running this application real-time and drawing the reference signal and the motor real signals. I run into several problems with regard to the calendar.

  1. when I change the size of the step of the simulation loop, the frequency of squares of reference also seems to change. For example. What step size = 1000, duration of pulse = 1 s. What step size = 100, pulse width = 0.1. (My pulse frequency is 1 Hz, Simulation clock - 10 kHz). How step size can affect the pulse width.

  2. can you explain the relationship between the DAQ, the Simulation step size loop sampling time, Loop Simulation period.

  3. If I want to collect different sets of data using sampling different hours, it's OK to change the sampling DAQ time without changing the size of the step of the simulation.

  Would also like to emphasize that the DAQmx calendar under sample clock mode is placed in front of the simulation loop and the output is connected to the loop simulation.

  Appreciate any help.

  Hello

  Maybe some screenshots of your code would help. Furthermore, what you have read your samples together with your DAQ screws?

  (1) If you have a waveform, the output is specified as:

  

  For example, if you change the size of the step of the simulation loop, you change the simulation time which are introduced into the signal generator and affecting the waveform that you see if you do not have a size quite small step to characterize the waveform that you generate.

  (2) sampling DAQ rate is the speed at which samples are taken on the acquisition of card data itself. The size of the simulation step, help. "Specifies the interval between the time when the ODE Solver evaluates the model and updates the results of the model, in a few seconds." Simulation loop, still using, "Indicates the amount of time that elapses between two subsequent iterations of the loop of control & Simulation.". " "Step size determine the value of t that is introduced to the functions you use in the loop simulation while the loop simulation period controls simply to how fast you change the following t value. The sampling rate of DAQ hardware is a clock of completely separate hardware controlling the analogue-digital on the DAQ card converter so that you can get a deterministic dt between the samples being acquired.

  (3) you can change the schedule for the acquisition of data, but you will need to restart each time the changes take effect. If you change the calendar of data acquisition and want your values to correlate with your simulation, you will need to change your size of step as well.

  -Zach

  -Zach

• differential equation

  Dear Sir

  I am a beginner in labview and I would like to solve two differential equations and field them over time:

  DX1/dt = (G - K * x 1 (t)) /V (t)

  dV (t) /dt = (1/((1-(((G-x1*(K-U))/(G-x0*(K-U)))^((U/(K-U)))-1))*U

  G = 7.8

  U = 0,166

  x 0 = 132

  VO = 432

  K = 2.02

  Could someone please help me and send the block diagram for these two equations.

  The graphs of these two variables have to be reduced over time. The graph of X 1 is of exponential decay.

  Hello Ahmad,

  I made a simple example and put it on our community page.  This example uses our ODE solver vis LabVIEW comes with 8 built in ODE solvers.  These are all linear system solvers.  It seems that your equations are not linear. I suggest using the LaPlace transforms to solve equations.

  Code example

• Solve the ODE which uses a max() function

  I have an ODE that I would like to solve in labview, but it's the max() for the third function OF. How can I integrate this into the Solver, RK4? I also apply it over a period of ten minutes (t here is in minutes), so I would put the RK4 Solver within some set time the end time to be 10 + loop with a start time register offset, or simply? I've included the variables + constants table for your reference.

  

  

  I do not understand your question about the error. Comments about all numerical values are already doubled.

  I found the basic problem. Column to 1 d array.vi returns an array containing a single element. This causes the Solver RK choke because it needs of 4 elements. The solution is to use only the Index table. This version converge in about 11 iterations.

  The solution seems to be sensitive to the value of h, so something's not quite yet. Fixing that may depend on your knowledge of what represent equations.

  I enclose the things that I've changed. In the f picker.vi I added the * as mentioned previously. I also reformatted some constants, although I think it was unnecessary. In the Main VI, I added a bunch of indicators so I could see what was going on. These indicators led me to the size of the array, I also added a waiting for me to see the results of each iteration. You will want to remove that in your final version.  I've implemented a "approximately equal" function to stop the loop. I put it as stop on an error.

  I consider calculate two options outside the loop and then simply select the one you want on the inside. No time to run, but if you need hundreds or thousands of iterations to solve the equations we can add.

  Lynn

• Optimize the time spent in the digital resolution of ODEs?

  I'm numerically solve an ODE to the RK4 VI. I need to use a size of fixed bearing that I need in order to save the values of synchronously. Running a time step now takes about 5 ms on average. I ran the ODE even under Mathematica and obtenu.2ms at the moment. Are are better over there of the digital solvers that I could use?

  
  

• solve the differential equation

  Hello

  I m trying to solve a simple equation using euler vi. But I have not yet. the equation is:

  (T) DH / DT = 1/A *(F-h/R). I m not understand what I need to plug on euler vi. I´v already took a look at the example of ode euler, but I continuously difficult. Please help me. Thank you.

  I guess that your real goal is to learn to use Euler's method as it is a fairly easy to solve analytically ODE.  Here's a quick example.

• How to solve the problem of 'ASM disk group is inaccessible' slave VM rac2?

  People,
  
  Hello. I want to install Oracle 11 g RAC 2 using 2 virtual machines (VM main rac1 and rac2 VM slave) with Oracle Linux 5.6 according to the website http://appsdbaworkshop.blogspot.com/2011/10/11gr2-rac-on-linux-56-using-vmware.html
  
  Grid and data base RAC have been installed successfully for VMS rac1 and rac2.
  I use the slave rac2 VM test data grid and CARS because rac1 disk is full.
  The problem is that the OCR file is not available or currupted in the rac2 VM slave. To know his reasons, I check permission on disc ocr as below:
  
  [ora11g@rac2 bin] $ pwd
  / U02/11g_db/ora11g/racdb/bin
  
  [ora11g@rac2 bin] $ srvctl start asm
  
  RPRC-1070: could not verify if the ora.asm resource is registered
  Cannot communicate with crsd
  
  [ora11g@rac2 rac2] $ pwd
  / u01/app/Grid/log/Rac2
  
  [ora11g@rac2 rac2] $ cat alertrac2.log
  
  Last lines:
  [/ u01/app/grid/bin/cssdagent (5779)] CRS - 5822:Agent ' / u01/app/grid/bin/cssdagent_root "disconnected from the server. Details at (: CRSAGF00117 :) in u01/app/grid/log/rac2/agent/ohasd/oracssdagent_root/oracssdagent_root.log.)
  2012-03-20 13:44:55.914
  [ohasd (5149)] CRS-2112: the service ODE started on node rac2.
  2012-03-20 13:44:58.588
  [ohasd (5149)] CRS - 8017:location: / etc/oracle/lastgasp has 72 Advisory reboot log files, 0 were announced and 0 errors
  2012-03-20 13:45:07.555
  [ohasd (5149)] CRS - 2772:Server "rac2" was awarded to 'Free' the pool.
  2012-03-20 13:45:10.108
  [ohasd (5149)] CRS-2302: failed to get profile negotiators. Error CLSGPNP_NO_DAEMON (the demon GPNPD does not work).
  2012-03-20 13:45:10.251
  [gpnpd (5368)] CRS - 2328:GPNPD began the rac2 node.
  2012-03-20 13:45:13.037
  [cssd (5443)] CRS - 1713:CSSD daemon is launched in cluster mode
  2012-03-20 13:45:37.132
  [cssd (5443)] CRS - 1707:Lease acquisition for node rac2 number 2 completed
  2012-03-20 13:45:37.727
  [cssd (5443)] CRS - 1605:CSSD file to vote is online: ORCL:ASMDISK3; details in u01/app/grid/log/rac2/cssd/ocssd.log.
  2012-03-20 13:45:37.986
  [cssd (5443)] CRS - 1625:Node rac1, number 1, was closed manually
  2012-03-20 13:45:37.991
  [cssd (5443)] CRS - 1605:CSSD file to vote is online: ORCL:ASMDISK2; details in u01/app/grid/log/rac2/cssd/ocssd.log.
  2012-03-20 13:45:38.633
  [cssd (5443)] CRS - 1605:CSSD file to vote is online: ORCL:ASMDISK1; details in u01/app/grid/log/rac2/cssd/ocssd.log.
  2012-03-20 13:45:56.956
  [cssd (5443)] CRS - 1601:CSSD Reconfiguration is complete. Active nodes are rac2.
  2012-03-20 13:46:00.557
  [ctssd (5834)] CRS-2403: the time synchronization Service on rac2 host Cluster is in observer mode.
  2012-03-20 13:46:00.576
  [ctssd (5834)] CRS-2407: the new Cluster Time Synchronization Service reference node is host rac2.
  2012-03-20 13:46:01.000
  [ctssd (5834)] CRS-2401: time synchronization Service Cluster started on host rac2.
  2012-03-20 13:46:11.097
  [crsd (5856)] CRS-1013: the location of the OCR in ASM disk group is inaccessible. Details in u01/app/grid/log/rac2/crsd/crsd.log.
  2012-03-20 13:46:12.085
  [ohasd (5149)] CRS - 2765:Resource 'ora.crsd' failed on the server "rac2.
  2012-03-20 13:46:13.338
  [crsd (5925)] CRS-1013: the location of the OCR in ASM disk group is inaccessible. Details in u01/app/grid/log/rac2/crsd/crsd.log.
  2012-03-20 13:46:14.217
  [ohasd (5149)] CRS - 2765:Resource 'ora.crsd' failed on the server "rac2.
  2012-03-20 13:46:15.438
  [crsd (5940)] CRS-1013: the location of the OCR in ASM disk group is inaccessible. Details in u01/app/grid/log/rac2/crsd/crsd.log.
  2012-03-20 13:46:16.313
  [ohasd (5149)] CRS - 2765:Resource 'ora.crsd' failed on the server "rac2.
  2012-03-20 13:46:17.539
  [crsd (5955)] CRS-1013: the location of the OCR in ASM disk group is inaccessible. Details in u01/app/grid/log/rac2/crsd/crsd.log.
  2012-03-20 13:46:18.392
  [ohasd (5149)] CRS - 2765:Resource 'ora.crsd' failed on the server "rac2.
  2012-03-20 13:46:19.537
  [crsd (5988)] CRS-1013: the location of the OCR in ASM disk group is inaccessible. Details in u01/app/grid/log/rac2/crsd/crsd.log.
  2012-03-20 13:46:20.468
  [ohasd (5149)] CRS - 2765:Resource 'ora.crsd' failed on the server "rac2.
  2012-03-20 13:46:22.636
  [crsd (6003)] CRS-1013: the location of the OCR in ASM disk group is inaccessible. Details in u01/app/grid/log/rac2/crsd/crsd.log.
  2012-03-20 13:46:23.615
  [ohasd (5149)] CRS - 2765:Resource 'ora.crsd' failed on the server "rac2.
  2012-03-20 13:46:24.781
  [crsd (6022)] CRS-1013: the location of the OCR in ASM disk group is inaccessible. Details in u01/app/grid/log/rac2/crsd/crsd.log.
  2012-03-20 13:46:25.713
  [ohasd (5149)] CRS - 2765:Resource 'ora.crsd' failed on the server "rac2.
  2012-03-20 13:46:26.885
  [crsd (6037)] CRS-1013: the location of the OCR in ASM disk group is inaccessible. Details in u01/app/grid/log/rac2/crsd/crsd.log.
  2012-03-20 13:46:27.799
  [ohasd (5149)] CRS - 2765:Resource 'ora.crsd' failed on the server "rac2.
  2012-03-20 13:46:29.021
  [crsd (6052)] CRS-1013: the location of the OCR in ASM disk group is inaccessible. Details in u01/app/grid/log/rac2/crsd/crsd.log.
  2012-03-20 13:46:29.925
  [ohasd (5149)] CRS - 2765:Resource 'ora.crsd' failed on the server "rac2.
  2012-03-20 13:46:31.136
  [crsd (6067)] CRS-1013: the location of the OCR in ASM disk group is inaccessible. Details in u01/app/grid/log/rac2/crsd/crsd.log.
  2012-03-20 13:46:32.040
  [ohasd (5149)] CRS - 2765:Resource 'ora.crsd' failed on the server "rac2.
  2012-03-20 13:46:33.247
  [crsd (6082)] CRS-1013: the location of the OCR in ASM disk group is inaccessible. Details in u01/app/grid/log/rac2/crsd/crsd.log.
  2012-03-20 13:46:34.172
  [ohasd (5149)] CRS - 2765:Resource 'ora.crsd' failed on the server "rac2.
  2012-03-20 13:46:34.173
  [ohasd (5149)] CRS - 2771:Maximum attempts to restart the resource 'ora.crsd '; does not restart.
  [ora11g@rac2 rac2] $
  
  The output of alertrac2.log, we have seen disk group ASM is inaccessible. So my question is:
  
  How to solve the problem of "ASM disk group is inaccessible" in the rac2 VM slave?
  
  
  Thank you.

  user8860348 wrote:
  People,

  Hello. Thanks much for the reply.

  Yes. I put the entry "SQLNET. AUTHENTICATION_SERVICES = (NTS)"input file sqlnet.ora.

  I ran the commands below:

  [ora11g@rac2 bin] $ pwd
  / u01/app/Grid/bin

  [ora11g@rac2 bin] $ ps - ef | grep pmon

  16219 ora11g 8602-0 12:29 pts/2 00:00:00 grep pmon

  [ora11g@rac2 bin] $

  [ora11g@rac2 bin] $ export ORACLE_SID = + ASM2
  [ora11g@rac2 bin] $. / sqlplus / as sysdba

  SQL * more: Production version 11.2.0.1.0 Fri Mar 23 12:33:15 2012

  Copyright (c) 1982, 2009, Oracle. All rights reserved.

  Connect to an instance is idle.

  SQL > startup pfile = ' / u01/app/grid/dbs/pfile ".
  ORA-01031: insufficient privileges
  SQL >

  Sign in as SYSASM as

  . / sqlplus / as sysasm
  >

  As we see above shows the command $ ps - ef | grep pmon, my question is:

  First of all, are ' 16219 8602 ora11g 0 "process ID?

  Secondly, we need to kill one by one? For examples: kill-9 ora11g? Kill-9 16219?

  Laughing out loud. It's not the running process.