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That's not a bug Radovan:

=>...For the free finding solutions, IC must be either 0 or 1
[1 to releive from "divide by zero"]<= ... {previous message}
Maybe you are not up to date vs Davide ?

Jean

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Thank you guys, these examples are very useful to fix the bugs in this plugin

I'm working to a new version of the code, almost totally refactored.
Looking at your examples seems there are several things to fix in my preprocessor; with some tweak, it is able to solve it.



now I just have to find some consistant way to make it working always

Wrote

Davide, any progress about this plugin and its new version?

Regards,
Radovan

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Maybe, I don't understand much in there ?

Jean

Page1 Unknown Solve.sm (30 KiB) downloaded 70 time(s).

• Just evaluate: displays result vector and executes embedded assignment
  
  
• Assign and evaluate in the same region: Error (symbolic evaluation reveals that the expression isn't executed but just stored as if it was inside line())
  
  
• Assign and evaluate in separate regions: displays result vector and executes embedded assignment upon display.
  
  
• Assign wrapped in eval() and evaluate in the same region: displays result vector and executes embedded assignment (here, eval() seems to be a friend of FindRoot())
  

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Should we generally avoid assignment with integrated evaluation for the time being?

Wrote

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Should we generally avoid assignment with integrated evaluation for the time being?

Yes, they should be avoided. There are several known issues while using implicit assignments, I plan to remove them when I'll have the possibility to commit a major update to this plugin.

Moreover now SMath Studio supports multiple assignments by matrices on LHS, therefore it shouldn't be a big loss.

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Be my guest if you want to solve it

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Be my guest if you want to solve it

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Be my guest if you want to solve it

Assuredly not a profitable guest !
I don't understand much in there.

Primer38-doomed.sm (39 KiB) downloaded 52 time(s).
Primer38-doomed_1.sm (44 KiB) downloaded 45 time(s).

Wrote

Here is the same problem solved in Mathcad

Regards,
Radovan

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Here is the same problem solved in Mathcad

Regards,
Radovan

Hi. Can you show the guess values for x and y? And k before Find too. I get a very different k value. Remember that for numerical procedures, guess values are part of the solution, not of the problem.
Thanks in advance.

Best regards.
Alvaro.

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This is a system of nonlinear algebraic equations. If one takes a look at the calculation here it is obvious that any gradient algorithm for solving this system will fail. Therefore, some non-gradient method might solve this (direct solving or some minimization procedure). There are some functions in the NonlinearSolvers plugin, but unfortunately, there is no update of them for a long time and many of them do not work anymore. All of these years I mentioned that we need here some well tested and robust library incorporated in SMath regarding these problems. There are no other plugins which will address these problems (AFAIK) and I am not sure that will ever be any.

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Did you enterenough decimals ?

Wrote

Hello Jean,

The solution is from Mathcad (Given/Find)
With an increased number of decimals.