Leo,
thank you very much, now it works perfectly.
Best Regards
Sergio Rossi
2009/6/26 Leo Butler <l.butler at ed.ac.uk>:
>
>
> On Fri, 26 Jun 2009, deltaquattro at gmail.com wrote:
>
> < Hi,
> <
> < I am having trouble with solving a simple linear system in Maxima:
> <
> < E(a,b):=integrate((f(x)-(a*g(x)+b))^2,x,0,1);
> <
> < e1(a,b):=diff(E(a,b),a,1);
> <
> < e2(a,b):=diff(E(a,b),b,1);
> <
> < linsolve([e1(a,b)=0, e2(a,b)=0], [a,b]);
> <
> < returns []. I also tried algsys (shouldn't be needed, but just in
> < case..) and the output is the same. Is there any workaround for this?
>
> Add the declaration
>
> declare(integrate,additive);
>
> and define
>
> e1(a,b):=expand(diff(...));
>
> and similarly for e2.
>
> This will work for you. The problem is that the coefficients are inside
> integrate(...) and you need them to be pulled out. The declare/expand
> combination does this.
>
> Leo
>
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>
>