Change log for Magma V2.10-9 (Released 10/6/2003)

Geometry

·An error in the Chabauty function for hyperelliptic curves has been fixed. The problem is exhibited with the example: J := Jacobian(HyperellipticCurve(2*x^6 - x^4 - 2*x^3 - 2*x^2 + 2*x - 3));D := elt<J | x^2 + 2/79*x - 181/79,3045/6241*x - 20521/6241, 2>;Chabauty(D,7);

·An error in MordellWeilGroup of an elliptic curve has been fixed. This could cause a crash if the group of another elliptic curve had been previously calculated and certain other conditions also held.

Incidence Structures

·A small improvement in subgraph construction: support and labels are now transferred from the supergraph to the subgraph.

·A bug arising when deleting graphs has been fixed.

Rings and Fields

·Some small improvements and bug fixes have been made in the automatic coercions between various p-adic rings and fields.

·A bug in GaloisImage for p â‰¥ 5 has been fixed.

System

·The memory management code for the Linux version has been rewritten, to work around a limitation of the Linux architecture, which previously restricted Magma to approximately 800 MB of system memory. Magma should now be able to access as much memory as possible.

·A memory leak caused when nested aggregate structures (such as sequences of tuples) were passed to procedures that modified them has been fixed.