Classic Fourier Series

[salvomic]

(01-31-2015 09:11 PM)Snorre Wrote:  Hello Salvo,

a program is always a good idea ;-)

Just two tips:

...

hi friend,
your tips are very welcome!
I'm changing my program in this way.
I'm still a newcomer in this programming language, so I love to learn more and more tips!

Yes, however, I would export a list of three arguments: a0 (however this one is always the same), ak, bk...

Last: doing so:

Code:


a0:=int(fun(t),t,0,2*PI)/(2*PI);
ak:=int(fun(t)*cos(k*t),t,0,2*PI)/PI;
bk:=int(fun(t)*sin(k*t),t,0,2*PI)/PI;

How can we avoid this error?
I set g:=x^2 then input fourcoeff(g(x),1) or fourcoeff(x^2,1) and I get "warning, evaluating invariable expression(value) like if expression was a function. You should write subst(x^2,x,t)"...
Sure I miss something else
I would better have the possibility to input both functions or expressions :-)

For the rest, I would also use the program (or the function we discussed above) with some "piecewise" functions.
So I tried to define a function for "square wave", f(t):=PIECEWISE(-π<t<0,-1,t=0,0,t=-π,0,t=π,0,0<t<π,1); this function seem to be ok, but if I use it with the program or with other integrate function I get "No case applies"...
Is this the way to use "Piecewise" function or I miss something?

Thank you!

Salvo