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IdealRayClassRep

Returns a representive of the class of an ideal in the ray class group.

Syntax:

r := IdealRayClassRep(I,m0,minf);

matrix
  r  
ideal
  I  
ideal
  m0  
list
  minf  
of integers/infinite primes

See also:  EltCon, OrderClassGroup, RayClassGroup, RayClassGroupCyclicFactors

Description:

Decomposes an ideal, or more exactly, the class of this ideal (that need to be coprime to {\goth{m}}_0) into a power product of the classes generating the whole ray class group. Based on the solutions for the discrete logarithm problem for class groups (He1) and for ray residue rings (see EltRayResidueRingRep), an exponent vector relative to the generators is computed.


Example:


kash> O := OrderMaximal(Order(x^2-2*x-5));
Generating polynomial: x^2 - 2*x - 5
Discriminant: 24 

kash> OrderClassGroup(O,500,"euler","fast");
[ 1, [ 1 ] ]
kash> m0 := 27*O;;
kash> minf := [2];;
kash> L := RayClassGroupCyclicFactors(m0,minf);
[ [ <[1344, 388]>, 3 ], [ <[1612, 444]>, 9 ] ]
kash> I := L[1][1];
<[1344, 388]>
kash> IdealRayClassRep(I,m0,minf);
[1 0]


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