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RayResidueRingRepToElt

Returns a canonical representative of an element of the multiplicative group of the residue class ring of a congruence module.

Syntax:

b := RayResidueRingRepToElt( r, m0, minf);

algebraic element
  b  
matrix
  r  
ideal
  m0  
list
  minf  
of integers/infinite primes

See also:  RayResidueRing, RayResidueRingCyclicFactors, EltRayResidueRingRep

Description:

This is the inverse to EltRayResidueRingRep. The function will compute the following product: \prod|{i=1}^l a|i^{ r|i} with a|i the multiplicative basis for (o/{\goth{m}}_0)^* as returned by RayResidueRingCyclicFactors.


Example:


kash> O := OrderMaximal(Order(Poly(Zx,[1,3,-4,7])));;
kash> m0 := 15*O;;
kash> a := Elt(O,[7,1,8]);;
kash> r := EltRayResidueRingRep(a,m0);
[20 65]
kash> b := RayResidueRingRepToElt(r,m0);
[7, 1, 8]


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