Re: How to evaluate the Laplacian of a function as a

*To*: mathgroup at smc.vnet.net*Subject*: [mg114373] Re: How to evaluate the Laplacian of a function as a*From*: Patrick Scheibe <pscheibe at trm.uni-leipzig.de>*Date*: Thu, 2 Dec 2010 05:41:12 -0500 (EST)

Hi, to understand whats happening and why this works please check carefully the difference between Set (=) and SetDelayed (:=) << VectorAnalysis` func[x_, y_] := 3/Pi*(1 - x^2 + y^2)^2 funcLapl[Xx_, Yy_] = Laplacian[func[Xx, Yy]] funcLapl[a, b] Cheers Patrick On Wed, 2010-12-01 at 02:15 -0500, Iliyan Georgiev wrote: > Hi, > > I have a stupid problem and cannot find a solution anywhere. I have > the function > > func[x_,y_] := 3/Pi*(1 - x^2 + y^2))^2 > > which I need the Laplacian of: > > funcLapl := Laplacian[func[Xx,Yy]] > > The Laplacian is computed correctly, but how can I treat the result as > a function? I want to be able to evaluate/plot the Laplacian. I tried > many things and I'm frustrated. My current solution is to manually > copy the derived Laplacian and create a function from that. It's > obviously not a good solution. > > Any suggestions? >