Change log for Magma V2.13-10 (Released 26/2/2007)

Coding Theory

·Some bugs in the computation of the minimum Lee weight for codes over 4 have been fixed.

Groups

·A bug in the reconstruction of p-group automorphisms on a second call to AutomorphismGroup has been fixed. Bug reported by Derek Holt.

·Internal errors when the BlocksAction routine for permutation groups was given an incorrect block system have been trapped. Bug reported by Derek Holt.

·A crash when IntegralGroup was given an infinite group argument has been fixed. This now gives a runtime error. Bug reported by Markus Grassl.

Interpreter

·A bad leak in the eval operator has been fixed. Reported by D. Holt.

Local Rings

·A bug that could cause some parentheses to be omitted when printing polynomials over some local rings has been fixed. Reported by J. Voight.

Matrices

·A bug in KernelMatrix for matrices over multivariate polynomial rings over the integers and having zero rows has been fixed. Reported by Andreas-Stephan Elsenhans.

Modules

·Missing checks for matrix spaces over rings with zero divisors have been inserted.

Monoids

·A crash when using a monoid with generator names assigned has been fixed. Bug reported by Klaus Brockhaus.

Number Fields

·Zeroes for orders and number fields returned the zeroes with not enough precision in the wrong ring (old reals).

·The embedding from cyclotomic fields, number fields and quadratic fields into real and complex fields was ignoring the precision of the target ring, the internal number field precision was used.

·An internal bug for user created prime ideals in relative extensions that could result in internal errors when the residue class fields of those ideals are used, has been fixed.

·A bug in indexform equations in arbitrary orders of cubic fields that would, in some cases, trigger an internal error has been fixed.

Polynomial Rings

·Localization for univariate polynomial rings over the rationals did not work when wrong arguments were being passed to it.

·Localization(RngMPol, RngMPol) is now implemented.

·Bugs in computing the squarefree factorization of polynomials over non-perfect fields have been fixed.

Residue Class Rings

·Any rational may now be coerced into Integers(1).