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suggestVariableOrder -- suggests a good variable ordering

Synopsis

Usage:

suggestVariableOrder I
Inputs:
- I, an ideal,
Outputs:
- a list, variable ordering

Description

This method suggests a good variable ordering. The ordering is chosen by finding a good chordal completion of its constraint graph.

i1 : G = cartesianProduct(cycleGraph 3, pathGraph 3);

i2 : I = edgeIdeal G

o2 = monomialIdeal (x x , x x , x x , x x , x x , x x , x x , x x , x x ,
                     1 2   1 3   1 4   3 4   2 5   2 6   3 6   2 7   4 7 
     ------------------------------------------------------------------------
     x x , x x , x x , x x , x x , x x )
      6 7   5 8   6 8   5 9   7 9   8 9

o2 : MonomialIdeal of QQ[x ..x ]
                          1   9

i3 : X = suggestVariableOrder I

o3 = {x , x , x , x , x , x , x , x , x }
       1   3   4   2   6   5   7   8   9

o3 : List

See also

constraintGraph -- constraint graph of a polynomial set
chordalGraph -- chordal completion of a graph

Ways to use suggestVariableOrder :

suggestVariableOrder(Ideal)

For the programmer

The object suggestVariableOrder is a method function.