problem with solving a system of equations

#1 Опубликовано: 17.08.2024 00:07:15

Prmtv

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Hello!

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

00.sm (9,79 КиБ) скачан 1021 раз(а).

Thanks!

#2 Опубликовано: 17.08.2024 05:49:32

Martin Kraska

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

00_Kr.sm (13,52 КиБ) скачан 1057 раз(а).

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 Опубликовано: 18.08.2024 00:20:41

Prmtv

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

00_Kr.sm (13,52 КиБ) скачан 1057 раз(а).

how to choose the right one initial guess?

#4 Опубликовано: 18.08.2024 04:15:52

overlord

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how to choose the right one initial guess?

What I can suggest is to use right solver.

#5 Опубликовано: 18.08.2024 19:25:46

Prmtv

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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 Опубликовано: 18.08.2024 19:51:08

overlord

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

My guess and and experience is they are ordered alphabetically.

#7 Опубликовано: 22.08.2024 23:23:22

Prmtv

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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 Опубликовано: 23.08.2024 00:05:06

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 Опубликовано: 23.08.2024 03:42:01

Prmtv

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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

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

The problem occurs when using the function "FindRoot"

#10 Опубликовано: 23.08.2024 04:11:17

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 Опубликовано: 26.08.2024 01:33:45

Prmtv

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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

Thanks!

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