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Num.ABM

Computes the border basis of an almost vanishing ideal for a set of points using the ABM algorithm.
Syntax
          
Num.ABM(Points:MAT, Epsilon:RAT):Object
Num.ABM(Points:MAT, Epsilon:RAT, Delta:RAT, ForbiddenTerms:LIST, NormalizeType:INT):Object

          

Description
Please note: The function(s) explained on this page is/are using the ApCoCoAServer. You will have to start the ApCoCoAServer in order to use it/them.

This command computes a border basis of an almost vanishing ideal for a set of points.

The current ring has to be a ring over the rational numbers with a standard-degree compatible term-ordering. The matrix Points contains the points: each point is a row in the matrix, so the number of columns must equal the number of indeterminates in the current ring. The following parameters are optional:

Example
Use P::=QQ[x,y,z];

Points := Mat([[1,0,0],[0,0,1],[0,0.99,0]]);
Res := Num.ABM(Points,0.1);

Dec(Res[1],2);

-- CoCoAServer: computing Cpu Time = 0.016
-------------------------------
["1 x +1.01 y +0.99 z -0.99  ", "1 z^2 -0.99 z +0.00  ", "1 yz ", "1 xz ", "1 y^2 -0.98 y -0.00  ", "1 xy "]
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See Also