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Local maxima of solution

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Dear all,
I use comsol to solving a certain EDP problem (Laplace equation for exemple in crown domain: 2D or 3D domain). The solution is noted 'u'.
I want to calculate the all local maxima of the solution 'u' but I dont know the convenable command comsol can I use.
Please does any one can help me.
Sincerly
Moncef Mahjoub

2 Replies Last Post 22 feb 2013, 11:46 GMT-5
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 22 feb 2013, 01:34 GMT-5
Hi

I would start considering ux =0 location (the du/dx=0) this should give you all maxima (and minima, then you probably want to consider uxx for the sign. Plotting the 2nd derivative might be quite step wise, so you could consider too to increase the discretization to third order

--
Good luck
Ivar
Hi I would start considering ux =0 location (the du/dx=0) this should give you all maxima (and minima, then you probably want to consider uxx for the sign. Plotting the 2nd derivative might be quite step wise, so you could consider too to increase the discretization to third order -- Good luck Ivar

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Posted: 1 decade ago 22 feb 2013, 11:46 GMT-5
Thank you very mach for your response.
please is there a comsol command that calculates ux=0 and uy=0. Otherwise, how can we do.
Sincerly,
MM
Thank you very mach for your response. please is there a comsol command that calculates ux=0 and uy=0. Otherwise, how can we do. Sincerly, MM

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