topic Re: Solving a bizzare equation in Mathcad

Solving a bizzare equation

avci — Thu, 03 May 2018 13:20:54 GMT

Can anyone help me solve this equation? I tried everything but couldn't manage it.

Re: Solving a bizzare equation

VladimirN — Sat, 23 Dec 2017 23:06:32 GMT

Please attach your Mathcad worksheet (in archive file format) to the message.

Re: Solving a bizzare equation

avci — Sun, 24 Dec 2017 05:22:15 GMT

Here it is.

Thanks in advance.

Re: Solving a bizzare equation

Werner_E — Sun, 24 Dec 2017 10:23:55 GMT

Why not use a numeric solve block?

But your function is rather beasty, being very steep and so guess value and value for CTOL are important.

Furthermore you'll notice that with th standard CTOL of 10^-3 the result is not excat (CM(R.0) != 0)

Also the used algorithm counts - only Levenberg-Marquardt will find a ssolution, Conjugate Gradient and Quasi-Newton won't.

Re: Solving a bizzare equation

avci — Sun, 24 Dec 2017 16:08:13 GMT

I also tried numerical solve block but it didnt work as well. The main problem with my code, I believe, was the initial guess as you suggested. I have never thought it would be that sensitive. I noticed the solution is not exact but exact enough since safety factor of 4.2 is already set.

Thanks for your help.