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gfanInterface :: groebnerFan

groebnerFan -- the fan of all groebner bases of an ideal

Synopsis

Description

i1 : R = QQ[symbol a..symbol f];
i2 : I = pfaffians(4, genericSkewMatrix(R,4))

o2 = ideal(c*d - b*e + a*f)

o2 : Ideal of R
i3 : P = groebnerFan(I)
This is the Gfan program for computing Groebner fans and tropical varieties.
Use the command "gfan list" to view all subcommands.
The command "gfan" is deprecate for computing all Groebner bases of an ideal.
Please use subcommand "gfan _bases" instead. Awaiting input. <Ctrl>-D to end.
LP algorithm being used: "cddgmp".
LP algorithm being used: "cddgmp".

o3 = PolymakeObject{...11...}

o3 : PolymakeObject
i4 : peek P

o4 = PolymakeObject{AMBIENT_DIM => 6                                            }
                    CONES => {{}, {0}, {1}, {2}, {0, 1}, {0, 2}, {1, 2}}
                    DIM => 6
                    F_VECTOR => {1, 3, 3}
                    LINEALITY_DIM => 4
                    LINEALITY_SPACE => | 1 0 0 0 0  -1 |
                                       | 0 1 0 0 -1 0  |
                                       | 0 0 1 0 1  1  |
                                       | 0 0 0 1 1  1  |
                    MAXIMAL_CONES => {{}, {0}, {1}, {2}, {0, 1}, {0, 2}, {1, 2}}
                    N_RAYS => 3
                    ORTH_LINEALITY_SPACE => | 1 0 -1 -1 0 1 |
                                            | 0 1 -1 -1 1 0 |
                    PURE => 1
                    RAYS => | -2 1  1  1  1  -2 |
                            | 1  -2 1  1  -2 1  |
                            | 1  1  -2 -2 1  1  |

Caveat

Requires loading of the Polymake package to make the PolymakeObject type available.

See also

Ways to use groebnerFan :