NLöseDgl für implizite Differentialgleichungen

FritzK shared this question 1 year 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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