#9263: Some special functions don't work with arbitrary precision
-----------------------------+------------------------------
       Reporter:  zimmerma   |        Owner:  jason, jkantor
           Type:  defect     |       Status:  new
       Priority:  major      |    Milestone:  sage-5.12
      Component:  numerical  |   Resolution:
       Keywords:             |    Merged in:
        Authors:             |    Reviewers:
Report Upstream:  N/A        |  Work issues:
         Branch:             |       Commit:
   Dependencies:             |     Stopgaps:
-----------------------------+------------------------------
Description changed by zimmerma:

Old description:

> {{{
> ----------------------------------------------------------------------
> | Sage Version 4.4.2, Release Date: 2010-05-19                       |
> | Type notebook() for the GUI, and license() for information.        |
> ----------------------------------------------------------------------
> sage: n(airy_ai(1),digits=100)
> 0.1352924163128813861423083153567858971655368804931640625000000000000000000000000000000000000000000000
> }}}
>
> Clearly the last digits are wrong. This is due to Maxima; currently we
> are not giving it bigfloats, and in any case some of the functions don't
> work with arbitrary precision.
>
> The following functions should be changed to a different default backend
> (mpmath probably):
> * `airy_ai` and `airy_bi` (will be fixed with #12455)
> * `spherical_bessel_j` (it also has a SciPy option, but it also truncates
> the precision)
> * `spherical_bessel_y` (same as `spherical_bessel_j`)
> * `spherical_harmonic`
> * the elliptic integrals
> * `spherical_hankel1` and `spherical_hankel2`
> * `hypergeometric_U` (PARI is implemented and works with arbitrary
> precision, but it's not the default)
> * `bessel_K` and `bessel_Y` (will be fixed with #4102)
> * `inverse_jacobi`

New description:

 {{{
 ----------------------------------------------------------------------
 | Sage Version 4.4.2, Release Date: 2010-05-19                       |
 | Type notebook() for the GUI, and license() for information.        |
 ----------------------------------------------------------------------
 sage: n(airy_ai(1),digits=100)
 
0.1352924163128813861423083153567858971655368804931640625000000000000000000000000000000000000000000000
 }}}

 Clearly the last digits are wrong. This is due to Maxima; currently we are
 not giving it bigfloats, and in any case some of the functions don't work
 with arbitrary precision.

 The following functions should be changed to a different default backend
 (mpmath probably):
 * `airy_ai` and `airy_bi` (will be fixed with #12455)
 * `spherical_bessel_J` (it also has a SciPy option, but it also truncates
 the precision)
 * `spherical_bessel_Y` (same as `spherical_bessel_j`)
 * `spherical_harmonic`
 * the elliptic integrals
 * `spherical_hankel1` and `spherical_hankel2`
 * `hypergeometric_U` (PARI is implemented and works with arbitrary
 precision, but it's not the default)
 * `bessel_K` and `bessel_Y` (will be fixed with #4102)
 * `inverse_jacobi`

--

--
Ticket URL: <http://trac.sagemath.org/ticket/9263#comment:13>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica, 
and MATLAB

-- 
You received this message because you are subscribed to the Google Groups 
"sage-trac" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
To post to this group, send email to [email protected].
Visit this group at http://groups.google.com/group/sage-trac.
For more options, visit https://groups.google.com/groups/opt_out.

Reply via email to