Magma V2.24-4 Patch Notes

Algebraic Function Fields¶

• Testing the zero ideal for being square is now handled.
• MinimalPolynomial has been fixed for non integral elements when it differs to the characteristic polynomial. Reported by F. Voloch.

Algebraic Number Fields¶

• Testing the zero ideal for being square is now handled.
• Computing GCDs of elements of quotients of an order of a number field by an ideal has been fixed.
• A crash in pFundamentalUnits has been fixed.
• A specialised implementation for Trace of elements of cyclotomic fields has been provided which will use less memory in large degree fields. Reported by J. Voight.

Algebraic Surfaces¶

• A number of bugs have been fixed in ResolveSingularSurface for blow-up desingularization and also in the IntersectionMatrix computation of intersection numbers for the blow-up divisors. The result of the bugs was that irreducible blow-up components were sometimes erroneously duplicated and that, because of both related and independent problems, intersection numbers were incorrect or would cause runtime errors. Both problems have now been fixed.

Curves¶

• The difference between a divisor and a place of a curve has been fixed when the base fields of the curves of the divisor and the place are different.

Cyclic Covers¶

• A problem with non-monic models has been fixed. Reported by S. Hashimoto.

Groups¶

• A crash in SemidirectProduct has been fixed.
• A crash in ClassicalMaximals (with type "U", dimension 16, field of characteristic 3, and normaliser or general flag set) has been fixed.

Hypergeometric Motives¶

• An improved recognition of the cyclotomic case for Jacobi motives has been applied, and an alternative method to reconstruct Euler factors from their p-adic roots is used in large degree. Noted by F. Rodriguez Villegas.

Integers¶

• A modification to the factorization routine has been applied to remove large powers more efficiently. Reported by M. Grassl.

Lattices¶

• The BKZ intrinsic now gives an error when stability problems are detected, rather than simply returning the partially reduced lattice.

Matrices¶

• The multiplication algorithm for matrices defined over GF(3) has been speed up in the AVX executable. The CUDA algorithm over the same type of matrices has also had a fix in large dimension.

Matrix Groups¶

• The Irreducible parameter on ChevalleyGroup for F4 in characteristic 3 now correctly returns the 25-dimensional representation, not a 26-dimensional one.

Modular Forms¶

• A problem with Basis for half-integral weight forms has been fixed, involving auxiliary calculations in trivial spaces. Reported by M. Somos.

Modular Symbols¶

• A problem with NewformDecomposition in square level has been patched. Reported by A. Sutherland.
• A numerical round-off problem with InnerTwists has been fixed. Reported by A. Sutherland.

Schemes¶

• Reduction to compute flat closures in projective space now works properly over number fields. Bug reported by J. Rouse.

System¶

• A crash in AttachSpec has been fixed. Reported by E. O'Brien/J. Maglione.