# sympow: Computes special values of symmetric power elliptic curve L-functions¶

## Description¶

SYMPOW is a package to compute special values of symmetric power elliptic curve L-functions. It can compute up to about 64 digits of precision.

## License¶

See the file src/COPYING

## Upstream Contact¶

SYMPOW does not appear to be maintained any longer. Mark Watkins, the package author, now works at Magma. Previous (possibly still usable) email is watkins@maths.usyd.edu.au

New upstream: https://gitlab.com/rezozer/forks/sympow

## Dependencies¶

GNU patch

## Special Update/Build Instructions¶

Some of the code is very dubious, and it is anyones guess really what the compiler does with it. For example, the following line exists in src/eulerfactors.c:

if ((HECKE) && (d==1)) return hecke_good(p,ap,m,v);

But since hecke_good is defined as returning void, it’s hard to know exactly how this code behaves. I would not be surprised by any bugs that might show up. I (David Kirkby) would personally not trust this code much at all.

This is a difficult package to maintain. A trac ticket (#9758) has been opened to implement Watkins-Delaunay’s algorithm for computing modular degrees in Sage. Once implemented, it should be possible to remove this package.

The package is configured such that the data files are in a directory below where ‘sympow’ is installed. If Sage is installed globally, then it will be impossible to create the data files without being root. This has been fixed in the Gentoo Linux distribution. Some information from Christopher can be seen on http://trac.sagemath.org/sage_trac/ticket/9703 This package will generate binary versions of all shipped datafiles, so these will work. However, creating totally new datafiles from scratch will not work.

## Type¶

standard

## Equivalent System Packages¶

arch:

```
$ sudo pacman -S sympow
```

conda:

```
$ conda install sympow
```

Debian/Ubuntu:

```
$ sudo apt-get install sympow
```

Fedora/Redhat/CentOS:

```
$ sudo yum install sympow
```

gentoo:

```
$ sudo emerge sympow
```

nix:

```
$ nix-env --install sympow
```

opensuse:

```
$ sudo zypper install sympow
```

See https://repology.org/project/sympow/versions

If the system package is installed, ./configure will check whether it can be used.