calculating 1F1

[maitra]

Very new to the FLINT library and trying to understand where the function to call 1F1 is. Sorry about the naivette.

[albinahlback]

No problem! I think it is under this section of the documentation. If you are only interested in the real-valued function, please see this part of the documentation instead.

[fredrik-johansson]

Adding to that, if you only care about machine-precision floats, there is a function here.

[maitra]

Thank you very much, @albinahlback and @fredrik-johansson -- I was looking at the source code trying to figure this out. I now see that the real version calls the complex version. Thanks again for the library!

[maitra]

No problem! I think it is under this section of the documentation. If you are only interested in the real-valued function, please see this part of the documentation instead.

From the above, I read that void arb_hypgeom_1f1_integration is recommended for large arguments, but a > 1 and b - a > 1 but I was wondering, what is recommended for large x and a > b > 1?

[albinahlback]

Why just not use the function arb_hypgeom_1f1 (aka arb_hypgeom_m)? Is there a reason for using that specific algorithm?

[maitra]

Why just not use the function arb_hypgeom_1f1 (aka arb_hypgeom_m)? Is there a reason for using that specific algorithm?

Oh, because x is large for me, therefore I was looking for some easy way to calculate or some approximation.

[albinahlback]

Ping @fredrik-johansson