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Re: Why does Derivative fail in this case?

  • To: mathgroup at smc.vnet.net
  • Subject: [mg96598] Re: Why does Derivative fail in this case?
  • From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
  • Date: Mon, 16 Feb 2009 16:42:59 -0500 (EST)
  • Organization: Uni Leipzig
  • References: <gnbkcl$3ej$1@smc.vnet.net>
  • Reply-to: kuska at informatik.uni-leipzig.de

Hi,

try:

g = f[#1, #2]*f[#1, #2] &;

And why SlotSequence[1] is different from Slot[1]
is self-explanatory


Regards
   Jens

Aaron Fude wrote:
> Hi,
> 
> This example is self-explanatory:
> 
> f[x_, y_] := x y
> g = f[##]*f[##] &;
> h = Derivative[1, 0][g];
> g[x, y]
> h[x, y]
> 
> I should expect that h[x, y] is 2 x y^2, but instead it is zero. How
> come?
> 
> Version 6.0
> 
> Many thanks in advance,
> 
> Aaron
> 


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