Raymond E. Rogers wrote:
> Doug Stewart wrote:
> <clip>
>>
>>
>>
>> Fx = 0 -10<x<-5
>> -5 -5<x<0
>> 5 0<x<5
>> 0 5<x<10
>>
>>
>>
>> |----------|
>> | |
>> | |
>> --------| | |----------
>> | |
>> |----------|
>>
>> thanks in advance
>>
>> Doug
>>
> Okay, sorry if I was talking down.
No you wern't talking down. I just added some background so that we
could get to the point faster :-)
> I never know.
> Somebody else mentioned doing the integrals in Maxima; one by one.
> Good practice but not what you buy a CAS for.
> I looked at the Fourier package and have doubts. It doesn't know
> unit_step, signum(),del();although it is happy to return del() ).
> demo(fourie)
> However it does know abs(). Although it does give a reasonable, if
> superficial, answer to fourier(diff(abs(x)),x,1); it
> doesn't seem to evaluate fourier(diff(abs(x-1/5),x,1) appropriately.
> In all it seems to need serious repair; but I hope somebody corrects
> me in this.
> It seems to fall back on integrate; but integrate doesn't seem to know
> about del(). I think, I am not sure.
> There is also fourier_elim ; but I have no idea what it does.
> The Laplace xform knows delta(x-a) it doesn't seem to do
> integrate(delta) which is what you need.
> Perhaps someone else can help.
> Sorry,
>
> RayR
>
>
My hand work is at
http://dougs.homeip.net/f2008/q10.pdfhttp://dougs.homeip.net/f2008/q10g.pdf
Thanks for your effort. We will have to do these without Maxima.
Doug