Wrote

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

Wrote

Maybe, I don't understand much in there ?

Jean

Page1 Unknown Solve.sm (30 КиБ) скачан 70 раз(а).

• 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())
  

Wrote

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.

Wrote

Be my guest if you want to solve it

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Be my guest if you want to solve it

Wrote

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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 КиБ) скачан 52 раз(а).
Primer38-doomed_1.sm (44 КиБ) скачан 45 раз(а).

Wrote

Here is the same problem solved in Mathcad

Regards,
Radovan

Wrote

Wrote

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.

Wrote

Did you enterenough decimals ?

Wrote

Hello Jean,

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