Re: collect derivatives

*To*: mathgroup at smc.vnet.net*Subject*: [mg23280] Re: [mg23259] collect derivatives*From*: Andrzej Kozlowski <andrzej at platon.c.u-tokyo.ac.jp>*Date*: Sun, 30 Apr 2000 21:13:32 -0400 (EDT)*Sender*: owner-wri-mathgroup at wolfram.com

on 00.4.30 11:05 AM, Robert at robert.schuerhuber at gmx.at wrote: > 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] > > ? > > thanks, robert > > Use patterns in Collect, e.g. In[1]:= (_) Collect[z[x] + u[x] z'[x] + u'[x] z'[x] + u[x] z''[x], z [x]] Out[1]= z[x] + (u[x] + u'[x]) z'[x] + u[x] z''[x] -- Andrzej Kozlowski Toyama International University Toyama, Japan http://sigma.tuins.ac.jp/