01-12-2012 03:50 AM
LV 6.1 is obsolete so you must upgrade experiment code to a newer version. There is a bug found in LV 8.2 that a particular system of equations given to the "Nonlinear System Solver.vi" gets the output of empty arrays. This error was solved in the new function:
http://zone.ni.com/reference/en-XX/help/371361H-01/gmath/nonlinear_system_solver/
It is suppose you can fix this problem changing the attached files in C:\Program Files\National Instruments\LabVIEW X.X\vi.lib\gmath\zero.llb, but this has been tested only in LV 8.2
In addition, when using the LabVIEW nD Nonlilnear System Solver VI with the variable "t", error -23001 occurs. Any other variable letter appears to work without error, but there doesn't appear to be anything that documents not using that particular variable with this VI.
01-12-2012 06:28 PM
I cannot save back to version 6.1.
When I use your Start and End values I get no outputs from either the old solver or the one in LV 2011. Both return 0 error also.
I implemented your formula in native LV functions rather than using the solver and found that the results using either the Start or End values are quite close to each other. Some rows are the same within 4 significant figures. I suspect that your set of equations may not have a valid solution.
Here are images of what I have done. The first shows the values calculated by the five formulas. The number above each column identifies the equations by the first constant in the formulas. The formulas to the right of the Numerical Values array indicate the portion of each formula shown in that row. The second row is the value of ln(constant/c) for example. The values of a, b, n, d, and c are those in Start.
The second image shows the block diagram showing how the constants were entered.
The third image shows the block diagram of the subVI which calculates the numerical values.
Lynn
01-13-2012 10:11 AM
I´m going to change the aspect of the equation, and I´m going to reduce the parameters to 3. I send you the results or the problems. 🙂
You told that you don´t have any error, also with the vi that I send you?. I don´t understand if you make one test with my version of the program or with the version of the solver of my program but in a newer version of the program. This is important because I run the program and I always have the -23001 error. why?.
Do you think that the formula is write in the right way?, I mean, I don´t know yet why with comas I have the error -23023 and with points the error -23001. Maybe the last error is because I use wrong characters in the equation.
Thank you for all.
Vicente.
01-13-2012 10:17 AM
Thank you Sendia for the information about the versions and the problem with the sub vi. I´m going to try to reduce the variables and if it doesn´t work, I´m going to try to run the program in the last version.
01-13-2012 10:33 AM
I change the point with comas, an I wire de numbres of trials and the program gives me error 0!!
Now I have the challenge of the solutions of the equation system. I´m going to try what I told you in the other post.
Vicente.
01-13-2012 12:50 PM
I am glad you are making progress!
Please let us know hwat you find.
Lynn