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Laplacian : laplacian

laplacian takes two arguments : an expression F of n real variables and a vector of these variable names.
laplacian returns the laplacian de F, that is the sum of all second partial derivatives, for example in dimension n = 3:

$\displaystyle \nabla^{2}_{}$(F) = $\displaystyle {\frac{{\partial^2 F}}{{\partial x^2}}}$ + $\displaystyle {\frac{{\partial^2 F}}{{\partial y^2}}}$ + $\displaystyle {\frac{{\partial^2 F}}{{\partial z^2}}}$

Example
Find the laplacien of F(x, y, z) = 2x2y - xz3.
Input :
laplacian(2*x^2*y-x*z^3,[x,y,z])
Output :
4*y+-6*x*z



giac documentation written by Renée De Graeve and Bernard Parisse