I have the expression of an equation in cartesian coordinates (x,y) I want to change it to curvilinear coordinates (n,s). Bear in mind in some paper I always find the expression of the Jacobien is J=1+nκ(s) where κ(s) is the curvature. Can someone help me to white the curl of a vector in the general curvilinear coordinates or maybe give me some references please?
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