       Re: Derivative

• To: mathgroup at smc.vnet.net
• Subject: [mg95872] Re: Derivative
• From: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>
• Date: Thu, 29 Jan 2009 05:52:08 -0500 (EST)
• Organization: The Open University, Milton Keynes, UK
• References: <glpgeg\$lin\$1@smc.vnet.net>

```In article <glpgeg\$lin\$1 at smc.vnet.net>,
"Cetin Haftaoglu" <cetin.haftaoglu at bam.de> wrote:

> I have a function
>
>                 Norton[arg_,exp_,nenner_]:= MCB[arg / nenner]^exp
>
> I want to define my own deviation of the function Norton,
> D[Norton[arg,exp,nen],y]:=dNdx[arg,exp,nen]
>
> arg depends on y.
>
> I have tried it with
>
>                 Derivative[1,0,0][Norton][arg_,n_,k_]:=dNdx[arg,n,k]
>
> But I get an error.

Assuming I have correctly understood what you want, define an upvalue
should do it. For instance,

In:= Norton /: D[Norton[arg_, n_, k_], arg] := dNdx[arg, n, k]

In:= UpValues[Norton]

Out= {HoldPattern[\!\(
\*SubscriptBox[\(?\), \(arg\)]\(Norton[arg_, n_, k_]\)\)] :> dNdx[arg,
n, k]}

In:= Norton[arg_, exp_, nenner_] := MCB[arg/nenner]^exp

In:= ?Norton

Global`Norton

Norton/:\!\(
\*SubscriptBox[\(?\), \(arg\)]\(Norton[arg_, n_, k_]\)\):=dNdx[arg,n,k]

Norton[arg_,exp_,nenner_]:=MCB[arg/nenner]^exp

Regards,
--Jean-Marc

```

• Prev by Date: Re: Conditional list indexing
• Next by Date: Re: Printing (v7)
• Previous by thread: Re: Derivative
• Next by thread: Taking the derivative of a summation