package-call

[Rafael Andraschko]

Hey guys

I'm a newbie learning FriCAS and I have a question about 'package-calling' a function.

Exploring the library I've tried using riemannZeta, but the exposed version seems to be a category (HyperDoc tells me that it comes from SpecialFunctionCategory) so I guess that's why it doesn't get numerically evaluated.

The other version comes from an unexposed package (FunctionalSpecialFunction), which I tried to package-call:

riemannZeta(0.5+%i)$FSPECF(Complex(Float),Complex(Float))

which has no valid type. The command ')d op riemannZeta' instructs me what the parameters of FSPECF would be, but I obviously didn't understand.

Generically, how to parametrize a more complex domain? Where to read to understand what is needed?

Thank you!

[oldk1331]

Hi,

(I didn't receive this message in mailbox, strange...)

I searched through source files, and found that riemannZeta

is purely symbolic, you can not evaluate it numerically at all.

- Best,

- Qian

[Ralf Hemmecke]

> (I didn't receive this message in mailbox, strange...)

Strange indeed. I was also surprised that I didn't get a message from
github when I opened an issue. But maybe the OP doesn't get notified,
which maybe OK.

> I searched through source files, and found that riemannZeta
> is purely symbolic, you can not evaluate it numerically at all.

Oh, I am relieved that it is not only me. I also looked through the code
and couldn't find a function that evaluates riemannZeta.

Looks like evaluation of special functions is implemented in DoubleFloat.

https://fricas.github.io/api/DoubleFloat

Look at the respective file sf.spad to find out which special functions
come with an evaluation.

Or maybe you look here...

https://github.com/fricas/fricas/blob/master/src/algebra/special.spad#L1

Sorry, that this will not be of much help.

Ralf