Overconvergent Modular Symbols: implement random_element()

d94aeda2-32aa-4629-a4ab-df146d2bcca0 commented 8 years ago

The Overconvergent Modular Symbols package contains some (buggy) code for creating random overconvergent modular symbols, but currently raises NotImplementedError. The existing code needs to be fixed and modified to handle general congruence subgroups.

CC: @roed314

Component: modular forms

Keywords: OMS, L-function, sd87

Author: Ander Steele

Branch/Commit: public/ticket/21557 @ 5c1b1d1

Issue created by migration from https://trac.sagemath.org/ticket/21557

d94aeda2-32aa-4629-a4ab-df146d2bcca0 commented 8 years ago

Commit: c21647b

d94aeda2-32aa-4629-a4ab-df146d2bcca0 commented 8 years ago

Branch: u/asteele/random_element

fchapoton commented 7 years ago

comment:2

one failing doctest, because you should import DirichletGroup

7ed8c4ca-6d56-4ae9-953a-41e42b4ed313 commented 7 years ago

Changed commit from c21647b to 202cc92

7ed8c4ca-6d56-4ae9-953a-41e42b4ed313 commented 7 years ago

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

202cc92 add DirichletGroup to imports

fchapoton commented 7 years ago

comment:4

one failing doctest:

File "src/sage/modular/pollack_stevens/space.py", line 715, in sage.modular.pollack_stevens.space.PollackStevensModularSymbolspace.random_element
Failed example:
    M.random_element(10)
Expected:
    Traceback (most recent call last):
    ...
    NotImplementedError
Got:
    Modular symbol of level 11 with values in Space of 11-adic distributions with k=2 action and precision cap 20

fchapoton commented 7 years ago

comment:5

Also you need to set the status to "needs_review" if you want this to enter sage.

fchapoton commented 7 years ago

comment:6

ping ?

7ed8c4ca-6d56-4ae9-953a-41e42b4ed313 commented 7 years ago

Changed commit from 202cc92 to 72da74e

7ed8c4ca-6d56-4ae9-953a-41e42b4ed313 commented 7 years ago

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

`40cd20c`	`Merge master into random_element`
`72da74e`	`Fix obsolete (and wrong) doctest.`

roed314 commented 7 years ago

Changed keywords from OMS, L-function to OMS, L-function, sd87

11d1fc49-71a1-44e1-869f-76be013245a0 commented 6 years ago

comment:10

The first thing I tried resulted in an error message:

sage: F = PollackStevensModularSymbols(Gamma0(11), 2)
sage: F.random_element()
---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
<ipython-input-4-074c74c306de> in <module>()
----> 1 F.random_element()
...
ValueError: You can only compute the valuation with respect to a integer larger than 1.

So did the second:

sage: D = OverconvergentDistributions(4, 7, prec_cap=10)
sage: F = PollackStevensModularSymbols(Gamma0(21), coefficients=D)
sage: F.random_element()
---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
<ipython-input-19-074c74c306de> in <module>()
----> 1 F.random_element()

/storage/masiao/sage/local/lib/python2.7/site-packages/sage/modular/pollack_stevens/space.pyc in random_element(self, M)
    758                 t += D[g] * manin.gammas[g] - D[g]
    759             else:
--> 760                 if g in MR.reps_with_two_torsion():  # What is MR ??
    761                     t -= D[g]
    762                 else:

NameError: global name 'MR' is not defined

fchapoton commented 6 years ago

New commits:

`75b2119`	`Merge branch 'u/asteele/random_element' in 8.4.b1`
`5c1b1d1`	`some details in #21557`

fchapoton commented 6 years ago

Changed branch from u/asteele/random_element to public/ticket/21557

fchapoton commented 6 years ago

Changed commit from 72da74e to 5c1b1d1

sagemath / sage

Overconvergent Modular Symbols: implement random_element() #21557