Fourier Series using fourie.mac



Leo Butler pisze:
> 
> On Mon, 27 Jul 2009, Rafa? Topolnicki wrote:
> 
> < Hi,
> < 
> < During testing Fourier Series Expansion in maxima I found a problem I 
> < can't cope with.
> < 
> < (%i3)                            load(fourie)
> < (%o3)         /usr/share/maxima/5.18.1/share/calculus/fourie.mac
> < (%i4)                         f(x) := abs(sin(x))
> < (%o4)                         f(x) := abs(sin(x))
> < (%i5)                    flist : fourier(f(x), x, %pi)
> <                                           2
> < (%t5)                              a  = ---
> <                                      0   %pi
> < 
> <                       cos(%pi n)   cos(%pi n)      1         1
> <                    2 (---------- - ---------- + ------- - -------)
> <                        2 n + 2      2 n - 2     2 n + 2   2 n - 2
> < (%t6)        a  = -----------------------------------------------
> <                n                         %pi
> < 
>  
> The easiest thing to do would be to add a line
> 
> %t6 : a[n] = if n=1 then 'limit( subst(n=_n,rhs(%t6)),_n,n ) else
> %rhs(%t6);
> 
> This should probably be caught by fourexpand.
> 
> Leo
> 
> 
i'm afraid it's doesn't. I still get the same error
(%i8) %t6:a[n] = if n=1 then 'limit(subst(n=_n,rhs(%t6)),_n,n) else 
%rhs(%t6);
                           cos(%pi n)   cos(%pi n)      1         1
                        2 (---------- - ---------- + ------- - -------)
                            2 n + 2      2 n - 2     2 n + 2   2 n - 2
(%o8)   a  = %rhs(a  = -----------------------------------------------)
          n         n                         %pi
(%i9) fourexpand(flis,x,%pi,1);

first argument not a list
#0: fourexpand(l=flis,x=x,p=%pi,nn=1)(fourie.mac line 180)
  -- an error.  To debug this try debugmode(true);


the same when instead of 'limit(subst(n=_n,rhs(%t6)),_n,n) I type simply 0.

RT