MathGroup Archive 2000

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: collect derivatives


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/




  • Prev by Date: Re: hating DSolve...
  • Next by Date: Re: Problem with Plot and Ticks-function
  • Previous by thread: RE: collect derivatives
  • Next by thread: NURBS ?