Opened 2 years ago

# Combinatorial designs: add some difference matrices and related objects — at Version 5

Reported by: Owned by: gh-Ivo-Maffei major sage-9.7 combinatorics symmetric_nets orthogonal_arrays transversal_designs difference_matrices dimpase, slelievre Ivo Maffei N/A u/gh-Ivo-Maffei/symmetric_nets 6c362d817d58b2b7db17f1420ddaf78a7cd6d20b

We add a few constructions of difference matrices whose lambda parameter is not 1.

We then modify the orthogonal arrays and transversal designs constructions to take advantage of these additions. Finally, we add a new function symmetric_net.

### comment:1 Changed 2 years ago by dimpase

I see failing doctests:

sage -t --warn-long 94.4 src/sage/combinat/designs/latin_squares.py  # 2 doctests failed
sage -t --warn-long 94.4 src/sage/combinat/designs/designs_pyx.pyx  # 3 doctests failed

### comment:2 Changed 2 years ago by git

• Commit changed from 5cd8a3c3671efc12e6a511a1b79c854111f0b296 to 6c362d817d58b2b7db17f1420ddaf78a7cd6d20b

Branch pushed to git repo; I updated commit sha1. New commits:

 ​6c362d8 fixed old doctests and bugs

### comment:3 Changed 2 years ago by dimpase

Do you run tests using GitHub Actions? (see #29401 for details)

In your code, to build docs, one needs

• ## src/sage/combinat/designs/orthogonal_arrays.py

 a def symmetric_net(n, lmbda=1, check=True, existence=False): Set to True by default - existence -- bolean. Instead of returnig a symmetric net, return: - True -- such a net can be constructed by Sage - False -- no such a net exists - Unknown -- Sage does not know how to build such a design so such design may or may not exist - True -- such a net can be constructed by Sage - False -- no such a net exists - Unknown -- Sage does not know how to build such a design so such design may or may not exist EXAMPLES::
• ## src/sage/combinat/designs/difference_matrices.py

 a def subgroup_construction(g,k,lmbda,existence=False): - g,k,\lambda -- (integers) parameters of the difference matrix to construct - existence -- (boolean) instead of building the design, return: - True if Sage can build the difference matrix using the subgroup construction - False if Sage can't build the difference matrix using this construction Note that Sage may be able to build such difference matrix in other ways - True if Sage can build the difference matrix using the subgroup construction - False if Sage can't build the difference matrix using this construction Note that Sage may be able to build such difference matrix in other ways EXAMPLES::

(sphinx is very sensitive to correct indentation)

### comment:4 Changed 2 years ago by mkoeppe

• Milestone changed from sage-9.1 to sage-9.2

Batch modifying tickets that will likely not be ready for 9.1, based on a review of the ticket title, branch/review status, and last modification date.