On Thu, 2006-11-23 at 11:42 +0800, Wang Yuheng wrote:
> Code:
> (%i1)eq:'diff(%phi,t);
> (%o1)0
>
> Why?
Because %phi is a predefined constant (the golden mean); in
the same way that %pi is also predefined:
(%i1) %phi, numer;
(%o1) 1.618033988749895
(%i2) %pi, numer;
(%o2) 3.141592653589793
that means that the notation %alpha, %beta,... is not a good
way to represent the Greek alphabet, because it collides with
the syntax for constants.
Jaime Villate