Change log for Magma V2.12-16 (Released 8/11/2005)

Class Fields of Number Fields

·A problem in IsNormal with parameter All that would cause an infinite recursion if the conductor is not invariant under the automorphims of the base field has been fixed.

·A bug in IsNorm has been fixed - the function would occasionally return false wrongly.

Elliptic Curves

·A bug in the discrete logarithm that sometimes caused the algorithm to fail has been fixed.

·Points on E(Q) with p dividing the coordinates' denominators may now be coerced into E(Fp) (the result is the identity element).

·A bug in the SEA algorithm that sometimes caused it to fail with the error message "not enough terms to determine poly" has been fixed.

Geometry

·Several bugs in scheme maps involving product or weighted projective space have been fixed. In particular, the internal checking of inverse equations and the check for map equality.

·The EllipticCurve(C,point/place) and Conic(C) parametrisation intrinsics have been fixed to work for non-planar curves C.

·A number of small improvements have been made to the hypersurface and singularity checking intrinsics.

Groups

·A bug in the matrix group soluble radical routines has been fixed. Bug reported by Derek Holt.

Rings

·A problem in IsPID, IsEuclidean and related functions was solved. Those functions tended to return true in a large number of situations where "unkown" would have been more apropriate.