Second derivatives

*To*: mathgroup at smc.vnet.net*Subject*: [mg128516] Second derivatives*From*: Bruce McGough <bruce.mcgough at gmail.com>*Date*: Fri, 26 Oct 2012 23:47:51 -0400 (EDT)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*Delivered-to*: l-mathgroup@wolfram.com*Delivered-to*: mathgroup-newout@smc.vnet.net*Delivered-to*: mathgroup-newsend@smc.vnet.net

According to the documentation, D[f,{list,n}) should give the n-th order tensor capturing the corresponding Taylor coefficient. This doesn't seem to work in the following example: G[x_] := F[h[x]]; D[G[{x1, x2}], {{x1, x2}, 2}] The correct answer is given by D[D[G[{x1, x2}], {{x1, x2}}], {{x1, x2}}] Note that for an "abstract function H, D[H[{x1, x2}], {{x1, x2}, 2}] = D[D[H[{x1, x2}], {{x1, x2}}], {{x1, x2}}] Any explanation would be very helpful.