# Verifying extracted curve fitting parameters.

Posted 9 years ago
4586 Views
|
5 Replies
|
2 Total Likes
|
 Hello,Below is my script for finding curve fitting parameters R1,R2,R3,R4,C1,C2,C3,C4.How do I verify whether my extracted parameters are correct or not?The script is attached below with the file name thetajc.Thanks,Ram Attachments:
5 Replies
Sort By:
Posted 9 years ago
 Hey Thanks Chris! You're a rockstar! This works pretty well and the numbers seem realistic!!You made my day!
Posted 9 years ago
 The outter List layer of your data was giving FindFit some heartburn. I had to remove that with First. The result of FindFit is replacement rules of the form {R1 -> val1, R2 -> val2, R3 -> val3, ...}. These rules will directly replace the matching paramaters in your model formula md1. This result I call solution numbe one, sol1. To visualize the performance of the solution, Show the data and the Plot of the fitted curve together.sol1 = mdl /. FindFit[First@datav, mdl, RC, var]Show[ListPlot[datav, PlotRange -> All], Plot[sol1, {t, 0, 2}, PlotStyle -> Red]]
Posted 9 years ago
 Hey Chris, I had one last question. Is there a way I can restrict the range of the fitting variables to a predetermined range? e.g. let's say I want to limit the range of following variablesR1 = {0.0001,1}R2 = {0.1,5}R3={0.001,1}R4={0.1,100}C1={0.00001,0.00000001}C2={0.0001,0.1}C3={0.01,10}C4={0.001,10}Is it possible to restrict the variables in these ranges. I'm looking at the help files to figure this out!
Posted 9 years ago
 In this https://reference.wolfram.com/mathematica/ref/FindFit.htmlClick on Scope about half way down the pageand then click just below that on Constraints and Starting Valuesto see an example showing how to restrict ranges of variables.
Posted 9 years ago
 Thanks Bill