Re: On constants and D's behaviour
- To: mathgroup at smc.vnet.net
- Subject: [mg52460] Re: On constants and D's behaviour
- From: "Steve Luttrell" <steve_usenet at _removemefirst_luttrell.org.uk>
- Date: Sun, 28 Nov 2004 01:06:41 -0500 (EST)
- References: <co97pg$gub$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
You need to use Dt rather than D.
Thus
Dt[a,x]
gives
Dt[a,x]
whereas
Dt[a,x,Constants\[Rule]{a}]
gives
0
Steve Luttrell
"Nicolas Girard" <nicolas.girard at strasbourg.fr> wrote in message
news:co97pg$gub$1 at smc.vnet.net...
> Dear people,
> just a thought, from a frustrated mind:
>
> given that one can explicitely tell a symbol is a constant by modifying
> its attributes, then why the hell doesn't the partial derivative D take
> advantage of it, and treat nonconstant symbol as.... nonconstants, by
> default ??
>
> Cheers,
> Nicolas
>