Changing variables




Raymond Toy wrote:
> Moby wrote:
>   
>> I have what is probably a very simple question.  I have a function 
>> defined in Maxima, say the following:
>>
>> G(s) := 1/(3*s^2+2*s+1)
>>
>> Now I would like to define a variable r such that
>>
>> r^2 = 3*s^2
>>
>> and then define G(s) in terms of this new variable r.  How does one go 
>> about achieving this in Maxima?
>>     
>
> Perhaps this will help:
>
> subst([s = r/sqrt(3)], 1/(3*s^2+2*s+1))
> -> 1/(r^2+2*r/sqrt(3)+1)
>
> Ray
>
>
>   
Many thanks Raymond - is it possible to have Maxima itself work out the 
first paramter, namely the value of s in terms of r?

Thanks again.

-- 
--Moby

They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety.  -- Benjamin Franklin