problem with solving a system of equations

#1 Publicado: 17/8/2024 0:07:15

Prmtv

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Hello!

Such a problem appeared. Please tell me what's the matter

00.sm (9,79 KiB) descargado 1568 vez(es).

Thanks!

#2 Publicado: 17/8/2024 5:49:32

Martin Kraska

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roots() in this case needs a custom initial guess.

00_Kr.sm (13,52 KiB) descargado 1641 vez(es).

2024-08-17 00_46_56-SMath Solver - [00.sm_].png

Technische Mechanik mit SMath Studio: https://link.springer.com/book/10.1007/978-3-658-50592-9

#3 Publicado: 18/8/2024 0:20:41

Prmtv

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Wrote
roots() in this case needs a custom initial guess.

00_Kr.sm (13,52 KiB) descargado 1641 vez(es).

how to choose the right one initial guess?

#4 Publicado: 18/8/2024 4:15:52

overlord

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Wrote
how to choose the right one initial guess?

What I can suggest is to use right solver.

#5 Publicado: 18/8/2024 19:25:46

Prmtv

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Wrote

Wrote
how to choose the right one initial guess?

What I can suggest is to use right solver.

how is the order of output of variables determined? From function "Unknowns"?

#6 Publicado: 18/8/2024 19:51:08

overlord

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Wrote
how is the order of output of variables determined? From function "Unknowns"?[/attach]

My guess and and experience is they are ordered alphabetically.

#7 Publicado: 22/8/2024 23:23:22

Prmtv

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Wrote

Wrote
how to choose the right one initial guess?

What I can suggest is to use right solver.

Thanks!

But when creating exe-file required variables a, b, B, t = 1. Why does this happen? Or is this a feature of the plugin "Nonlinear solvers"?

#8 Publicado: 23/8/2024 0:05:06

overlord

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I can't know what you have done without your sheet.
However, this was not an issue when I saved it as an exe.

Regards

#9 Publicado: 23/8/2024 3:42:01

Prmtv

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Wrote
I can't know what you have done without your sheet.
However, this was not an issue when I saved it as an exe.

Regards

If I use the function "al_nleqsolve" then everything really works

The problem occurs when using the function "FindRoot"

#10 Publicado: 23/8/2024 4:11:17

overlord

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It is due to some bug or miscode for FindRoot().
Or this is totally SMath result parse method.
Your solution (A) is stored symbolic.
Make it totally numeric by eval().
Exe file can show correct results after that.

Regards

#11 Publicado: 26/8/2024 1:33:45

Prmtv

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Grupo: User

Wrote
It is due to some bug or miscode for FindRoot().
Or this is totally SMath result parse method.
Your solution (A) is stored symbolic.
Make it totally numeric by eval().
Exe file can show correct results after that.

Regards

Thanks!

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