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Calling matlab function in comsol

Vignesh Kumar Devendiran

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Hi,

I am using Coefficient form Pde interface to solve a system of PDEs. As the coefficients are non-linear messy expressions and they are functions of the gradients of the dependent variables and the parameters, I would like to group certain terms in the coefficients and call them through matlab functions. Example, if the variables are u,v,and w and if one of the coefficient looks like ux*(vy+wx+uy^2+vx*vy) (say), i would like to call vy+wx+uy^2+vx*vy as a matlab function and define the that coefficient to be ux*T(arguments).

I followed everything that is prescribed in the documentation and what I don't understand is this, how to define the derivatives of the matlab function that i have called? It is said in the document that the derivatives are nothing but the partial derivatives with respect to the input arguments. In the above example, there are 4 input arguments for the function, so i am expected to define the Jacobian is it?

Could someone clarify what has to defined as the derivatives ?

0 Replies Last Post 26.10.2014, 11:41 GMT-4
COMSOL Moderator

Hello Vignesh Kumar Devendiran

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