NLöseDgl für implizite Differentialgleichungen

FritzK shared this question 11 months ago
Answered

Hallo,

muss man ein Differentialgleichungssystem erst nach den (höchsten) Ableitungen auflösen oder kann NLöseDgl auch mit der implizierten Form umgehen. Mein Problem hat die Form:

M(y)*y' = f(y)

Muss man erst M^(-1)*f(y) bilden?

Comments (5)

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Please post the exact equation you are trying to solve

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Hallo Michael,

attached please find the two differential equations in the original format (similar to the problem of a double pendulum).

Files: Dgln.pdf
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Do you want to solve it with some numbers in? Can you post an example?

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attached please find an example, but I solved the equations manually for of phi_1" and phi_2" before coding in Geogebra. This is a valid procedure in my opinion, but it becomes very tedious for larger problems. The question is: is it also possible to retain terms with phi_1" and phi_2" in the functions as argument of NLöseDGl..

Thank you for your interest!

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Sorry, all terms sent to NSolveODE() must be numeric

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