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Second derivatives

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  • Subject: [mg128516] Second derivatives
  • From: Bruce McGough <bruce.mcgough at>
  • Date: Fri, 26 Oct 2012 23:47:51 -0400 (EDT)
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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.

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