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Re: collect derivatives

  • To: mathgroup at smc.vnet.net
  • Subject: [mg23350] Re: collect derivatives
  • From: Eckhard Hennig <hennig at itwm.uni-kl.de>
  • Date: Thu, 4 May 2000 02:59:17 -0400 (EDT)
  • Organization: ITWM
  • References: <8eg6bb$h2f@smc.vnet.net>
  • Sender: owner-wri-mathgroup at wolfram.com

Robert schrieb in Nachricht <8eg6bb$h2f at smc.vnet.net>...
>is there a way to use "collect[]" to collect all terms with a specific
>derivative, e.g. to produce something like
>
>z''[x] u[x] + z'[x] (u'[x]+u[x]) + z[x]
>


Yes, you can use Collect as follows:

Collect[yourexpr, z[x] | Derivative[_][z][x]]

-- Eckhard

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Dr.-Ing. Eckhard Hennig        mailto:hennig at itwm.uni-kl.de
Institut fuer Techno- und Wirtschaftsmathematik e.V. (ITWM)
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