Raymond Toy <toy@rtp.ericsson.se> writes:
> (C1) sinc(x) := if (x = 0) then 1 else sin(x)/x;
>
> SIN(x)
> (D1) sinc(x) := IF x = 0 THEN 1 ELSE ------
> x
[...]
> (C4) sinc(x);
>
> SIN(x)
> (D4) ------
> x
>
> Well, that's not right.
x evaluates to itself, so it is certainly not 0.
Perhaps you want something like
sinc(x) := if asksign(abs(x)) = 'zero then 1 else sin(x)/x;
Maybe you can use ASSUME to avoid Maxima asking the user.
Wolfgang