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Gremlins in my mathcad - data analysis in nonlinear regression

VorazbekUT
1-Visitor

Gremlins in my mathcad - data analysis in nonlinear regression

Hello, I'm having a problem with a Mathcad file - I am able to get the mathcad file to work if I separate it into two different files. However, in the same file it gives me an error about a variable being undefined. I'm not sure what's up with this. It's a first order absorption and elimination problem.

I've attached the files to show what the second part of the program is suppose to do and what it does if it works. I tried changing the variable names and references but something strange that I can't figure out is happening. I would appreciate any advice or wisdom on the matter.

ACCEPTED SOLUTION

Accepted Solutions
Werner_E
25-Diamond I
(To:VorazbekUT)

The reason that the Find() at the end of your gremlin sheet is failing is the superfluous "Given" at the top of your sheet after the definition of C.min. There is no closing Find, Odesolve, maximize, minerr, etc. for this given and so you can delete it and at least Find() will give you a solution.

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6 REPLIES 6

I hope same problem is here http://twt.mpei.ac.ru/TTHB/New-Chem-Kin/En-ChemKin.html

I witll find it.

But may be so:

tt.png

Some correction for the plot in "7.7works" worksheet can be found in attachment.

Steven Clise wrote:

I've attached the files to show what the second part of the program is suppose to do and what it does if it works.

ttgiven.png

You have a factor of 2 missing in h(D) - see below. Also, I'm not sure that your Tmax in "gremlins" matches any t in "works".

Alan

deriv.PNG

Werner_E
25-Diamond I
(To:VorazbekUT)

The reason that the Find() at the end of your gremlin sheet is failing is the superfluous "Given" at the top of your sheet after the definition of C.min. There is no closing Find, Odesolve, maximize, minerr, etc. for this given and so you can delete it and at least Find() will give you a solution.

This is what was causing my problem, thank you! I must have absent mindedly typed it and forgot it was there. I was originally going to solve the first part with conditions rather a root finder, thanks!

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