Hello,

I want to use the spline options in the SavitzkyGolayFilter, but I don't understand the description in the Maple help. Can someone give me Sytax examples? I would also like to specify the 1st and 2nd derivatives of the endpoints.

I am grateful for any help!

Why does Maple 2023.x not evaluate to Phi := -b in the following example?

> restart:
> z:=-a*exp(-I*b):
> Phi:=simplify(evalc(argument(z)));
               Phi := arctan(a sin(b), -a cos(b))

Since Maple forms the main value of arctan(y, x), would have to be
Phi=arctan(a sin(b), -a cos(b))=arctan((a sin(b))/(-a cos(b)))=arctan(-tan(b))=-b.

Is the full evaluation not implemented for some reason or what did I miss?