Re: Curl and Div problems

*To*: mathgroup at smc.vnet.net*Subject*: [mg115526] Re: Curl and Div problems*From*: Bob Hanlon <hanlonr at cox.net>*Date*: Thu, 13 Jan 2011 03:29:18 -0500 (EST)

Use the defined coordinate system Needs["VectorAnalysis`"] sub = Thread[{x, y, z} -> Coordinates[]] {x -> Xx, y -> Yy, z -> Zz} D[x^2 y, x] + D[x z, y] + D[x^2 y^3, z] 2 x y Div[{x^2 y, x z, x^2 y^3} /. sub] /. (Reverse /@ sub) 2 x y Div[{Xx^2 Yy, Xx Zz, Xx^2 Yy^3}] 2 Xx Yy Curl[{x^2 y, x z, x^2 y^3} /. sub] /. (Reverse /@ sub) {-x + 3*x^2*y^2, -2*x*y^3, -x^2 + z} Curl[{Xx^2 Yy, Xx Zz, Xx^2 Yy^3}] {-Xx + 3*Xx^2*Yy^2, -2*Xx*Yy^3, -Xx^2 + Zz} Bob Hanlon ---- sean k <seaninsocal at gmail.com> wrote: ============= I'm having problems with VectorAnalysis package. Within the documentation center, the package loads and works fine. But in a notebook, it seems to highlight Curl in red and neither Div or Curl works properly. Needs["VectorAnalysis`"] {D[x^2 y, x] + D[ x z, y] + D[ x^2 y^3, z]} Div[{x^2 y, x z, x^2 y^3}] gives different answers. {2 x y} 0 Curl[{x^2 y, x z, x^2 y^3}] gives {0,0,0} I'm on windows vista home edition, 64 bit, Mathematica 8.0. Does anyone else have this problem?