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OrderTraceMat

Returns the trace matrix of the order.

Syntax:

M := OrderTraceMat(o);

Matrix
  M  
order
  o  

Description:

OrderTraceMat returns the the trace matrix of the given order o. Let o be given by a (pseudo) basis omega|1, … , omega|n (we ignore the coefficient ideals here). The OrderTraceMat M = (\Tr(omega|i omega|j))_{i,j}.


Example:

Extracting the equation order of an arbitrary order.

kash> O := OrderMaximal(Poly (Zx,[1,0,-186,0,13097,0,-412704,0,4946176]));
   F[1]
    |
   F[2]
  /
 /
Q
F  [ 1]     Given by transformation matrix
F  [ 2]     x^8 - 186*x^6 + 13097*x^4 - 412704*x^2 + 4946176
Discriminant: 60050488100625 

kash> M := OrderTraceMat(O);
> [      8       0     186       4    1120     657     774     387]
[      0     372     186    2426     186   24657       0    5304]
[    186     186    4294    1306   24471   26711   16664   10984]
[      4    2426    1306   15364    1773  147638     387   32097]
[   1120     186   24471    1773  133394   91728   89382   47343]
[    657   24657   26711  147638   91728 1282603   53410  298835]
[    774       0   16664     387   89382   53410   59566   29783]
[    387    5304   10984   32097   47343  298835   29783   74701]


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