CoCalc Shared Filessupport / 2015-02-21 elkies.sagews
Authors: Harald Schilly, ℏal Snyder, William A. Stein
Description: Examples for support purposes.

In email from Noam about my birthday:

y^2 = x^8 - 4*x^7 - 8*x^6 + 10*x^5 + 20*x^4 + 8*x^3 - 15*x^2 - 20*x - 8

R.<x> = QQ[]
C = HyperellipticCurve(x^8 - 4*x^7 - 8*x^6 + 10*x^5 + 20*x^4 + 8*x^3 - 15*x^2 - 20*x - 8)

C.geometric_genus()

3
genus2reduction(0, x^8 - 4*x^7 - 8*x^6 + 10*x^5 + 20*x^4 + 8*x^3 - 15*x^2 - 20*x - 8)

Error in lines 1-1 Traceback (most recent call last): File "/projects/4a5f0542-5873-4eed-a85c-a18c706e8bcd/.sagemathcloud/sage_server.py", line 873, in execute exec compile(block+'\n', '', 'single') in namespace, locals File "", line 1, in <module> File "sage/misc/lazy_import.pyx", line 358, in sage.misc.lazy_import.LazyImport.__call__ (build/cythonized/sage/misc/lazy_import.c:3230) File "/usr/local/sage/sage-6.4/local/lib/python2.7/site-packages/sage/interfaces/genus2reduction.py", line 505, in __call__ raise ValueError("P (=%s) must have degree at most 6"%P) ValueError: P (=x^8 - 4*x^7 - 8*x^6 + 10*x^5 + 20*x^4 + 8*x^3 - 15*x^2 - 20*x - 8) must have degree at most 6