add the function is_prime_of_good_reduction

[Saher-Amasha]

the functions takes as input a dynamical system and a prime the function returns true if the prime is a prime of good reduction otherwise the function returns false

Depends on #31399

CC: @bhutz

Component: dynamics

Author: Saher Amasha, Safa Amasha

Branch/Commit: u/gh-Saher-Amasha/add_the_function_is_prime_of_good_reduction @ b9e0e8f

Reviewer: David Roe

Issue created by migration from https://trac.sagemath.org/ticket/31464

[Saher-Amasha]

Branch: u/gh-Saher-Amasha/add_the_function_is_prime_of_good_reduction

[Saher-Amasha]

New commits:

903bc3b

added the function is_prime_of_good_reduction:

[Saher-Amasha]

Commit: 903bc3b

[sagetrac-git]

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

3a8008b

removed the mod function because it allready has a ticket

[sagetrac-git]

Changed commit from 903bc3b to 3a8008b

[sagetrac-git]

Changed commit from 3a8008b to ac0b2ec

[sagetrac-git]

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

00a32f2	mod function for Dynamical Systems, the function takes as a parameter a prime p and returns the Dynamical System modulo p
ac0b2ec	Merge branch 't/31399/mod_function_for_dynamicalsystem' into t/31464/add_the_function_is_prime_of_good_reduction

[mkoeppe]

comment:5

Sage development has entered the release candidate phase for 9.3. Setting a new milestone for this ticket based on a cursory review of ticket status, priority, and last modification date.

[roed314]

comment:6

There's a test failure (no attribute mod_DS); you can click on the yellow question mark for details. There's also a plugin failure from style issues in your documentation (see also notes below).

Style changes:

• Use spaces after commas (and not before), and around +, *, / and = (except in keyword arguments like dS.mod(p=5)).
• Description should use "return" rather than "returns" and could probably be rephrased as "Whether this dynamical system has good reduction at the given prime"
• For mod, I would suggest using an EXAMPLES block rather than a TESTS block

Code questions/suggestions:

• Why do you need to copy self? I wouldn't expect any of these functions to change self in place.
• You shouldn't use a bare except, since it will catch KeyboardInterrupts. Better practice is to either catch the specific error type, or at least use except Exception:
• You can just return new_DS.degree_sequence(1)[0] == degree rather than using an if statement.
• Rather than looping over range(0, len(blah)) it's usually nicer to iterate over the object itself (e.g. for poly in df_p_all:)
• Even better: use a list comprehension like coefficients = [poly.coefficients() for poly in DS.defining_polynomials()].

[roed314]

Reviewer: David Roe