Magma V2.10-9 Patch Notes

Geometry¶

• An error in the Chabauty function for hyperelliptic curves has been fixed. The problem is exhibited with the example:

  J := Jacobian(HyperellipticCurve(2x^6 - x^4 - 2x^3 - 2x^2 + 2x - 3));\ D := elt<J | x^2 + 2/79x - 181/79,3045/6241x - 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 $p\ge 5$ 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.