### Finding a Subfunction

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I've been wracking my brain trying to figure out how to do this. Lets say I have a (simplified) trial function $f\left(x,y\right)=g\cdot f\left(c,y\right)$

`ƒ`(`x`,`y`)=`g`·`ƒ`(`c`,`y`) where c is some constant. How do I implement $f\left(c,y\right)$`ƒ`(`c`,`y`) ?
Community: FEniCS Project

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$\frac{dc_s}{dt}=\frac{1}{r^2}\cdot\frac{d}{dr}\left(D_sr^2\cdot\frac{dc_s}{dr}\right)$

dc_{s}dt=1r^{2}·ddr(D_{s}r^{2}·dc_{s}dr)where the only Neumann condition is:

$\frac{dc_s}{dr}=-\frac{jR_s}{Ds},r=1$

dc_{s}dr=−jR_{s}Ds,r=1and $j\left(c_s\left(x,r=1\right),c_e\left(x\right),\alpha_s\left(x\right),\alpha_e\left(x\right)\right)$

j(c_{s}(x,r=1),c_{e}(x),α_{s}(x),α_{e}(x)) , Rs, and Ds are defined on a separate 1D, 2D, or 3D mesh that has the same x as the first axis. Also $c_s,c_e,\alpha_s,\alpha_e,j$c_{s},c_{e},α_{s},α_{e},jform a system of PDE's. The reason for separating the $c_s$c_{s}domain is that it's considered a 'pseudo' dimension that doesn't change regardless of whether or not the remaining equations (physical dimensions) are in 1D or 3D, and so that the physical dimensions are representative of the battery I am trying to model. My main problem is translating j from the physical mesh to the pseudo mesh and translating $c_s\left(x,r=1\right)$c_{s}(x,r=1) from the pseudo mesh to the physical mesh such that I can define the system to be solved using the FEniCS nonlinear solver.Thanks!