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Re: Problem with ->



Hi Hans,

Since the full form of R'[s] in mathematica is

Derivative[1][R][s]

the rule

R[s] -> k s

won't fire. I can see two alternatives: One is to add the rule R'[s]->k,
and the other is to use a pure function approach:

R[s]/R'[s] /. R -> (k #&)

Carl Woll
Dept of Physics
U of Washington

On Sun, 8 Mar 1998, Hans Steffani wrote:

> 
> I want to substitute R[s] by k s.
> I tried:
> R[s] / R'[s] /. R[s] -> k s
> and got
> k s / R'[s]
> instead of the expected
> s
> 
> What am I doing wrong?
> 
> Hans Friedrich Steffani
> --
> Hans Friedrich Steffani
> Institut fuer Elektrische Maschinen und Antriebe, TU Chemnitz
> mailto:hans.steffani@e-technik.tu-chemnitz.de
> http://www.tu-chemnitz.de/~hfst/
> 
> 




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