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Implement direct product of cyclic groups #9694

Open 1d7ec08f-60ae-4512-91a6-8324c06eab9f opened 14 years ago

1d7ec08f-60ae-4512-91a6-8324c06eab9f commented 14 years ago

This will be a straightforward implementation of a direct product of cyclic groups, allowing students to experiment with basic notions of order, cyclicness, subgroups, etc.

CC: @williamstein @loefflerd @JohnCremona

Component: group theory

Issue created by migration from https://trac.sagemath.org/ticket/9694

1d7ec08f-60ae-4512-91a6-8324c06eab9f commented 14 years ago

Preliminary version, no doctests, etc

1d7ec08f-60ae-4512-91a6-8324c06eab9f commented 14 years ago
comment:1

Attachment: trac_9694-cyclic-group-product-v0.patch.gz

Patch is a rough cut. Requires something in the 4.5.2 alpha/rc series to work.

Posted here because of the hack to avoid having the __call__ function in the derived class not get called during the initialization.

Somewhere (once per invariant, I think) the creation of the optimized quotient module has a "self()" call that reaches all the way down into this class and if the optimized module is used for conversion, it just causes infinite recursion. (Also happens with saving _orig_gens but that is more obvious).

Need for the conversion is described more fully at #9695. Help or advice needed!

1d7ec08f-60ae-4512-91a6-8324c06eab9f commented 14 years ago
comment:2

This ticket can be killed. Work at #9773 supersedes it, while comments at #9695 explains some of my confusion.