Transpose text databases of reflexive polytopes for PALP

[novoselt]

We store reflexive polytopes in 2 and 3 dimensions as text files. The current version lists points as columns of matrices, but the default output for PALP is reversed and it gives cleaner code not handle two cases. The main point, however, is that it would be faster to construct reflexive polytopes lists in memory if files were written point by point.

The current code in Sage will accept both old and new versions of the database, while the new one I am (re)writing will work only with the new one.

There is also a comment in SPKG.txt (exactly five years old) that text files will be removed in favour of the also included binary ones. However this didn't happen yet and I think it makes sense to keep small lists in plain form which is so easy to parse directly in Python without relying on any database modules or PALP itself for that matter.

CC: @vbraun

Component: packages: standard

Author: Andrey Novoseltsev

Branch/Commit: f42ea43

Reviewer: Volker Braun

Issue created by migration from https://trac.sagemath.org/ticket/22400

[novoselt]

comment:1

Attachment: polytopes_db-20170220.tar.bz2.gz

[novoselt]

Branch: u/novoselt/transpose_lattice_polytopes

[novoselt]

Commit: f42ea43

[novoselt]

New commits:

f42ea43

Transpose databases of small reflexive polytopes

[vbraun]

Reviewer: Volker Braun

[vbraun]

Changed branch from u/novoselt/transpose_lattice_polytopes to f42ea43