Matroid database

Matroid 4.9.189890

Label4.9.189890
Idr4_n9_00000000000000000000000000000000000000000000000000000000000000000000000*******************************************************
Rank4
n9

Basic invariants

Bases55
Circuits66
Flats72
Cyclic flats3
Loops0
Connected components2
Automorphisms720
Beta invariant0
Girth3
Simpleyes
Connectedno
Uniformnot computed
Looplessyes
Colooplessno
Pavingno
Laminaryes
Nestedyes
Self dualno
Identically self dualno
Series parallelno
Transversalyes
Supersolvableno
Divisionally freeno
Orientableyes
Three linesnot computed

Representability

Characteristic setcharacteristic 0 and all primes [0]
Realizableyes
Realizable char0yes
Regularno
Binaryno
Ternaryno
Quaternaryno
Graphicno

Realization space

Statuscomputed_realization_space
Dimension of realization space1
Expected dimension over ℤnot computed
Components of realization spacenot computed
Free realization spaceyes
Principal idealyes
Birational typerational
how determined: birational type method: free_presentation
Birational type components
show
[
 {
  "dim": 7,
  "free_rank": 7,
  "torus_rank": 7,
  "core_dim": 0,
  "qbar_components": 1,
  "type": "rational",
  "reason": "free realization space"
 }
]
Good basisnot computed
Good basis v21,2,4,9

Geometry

Realization space: scheme simple core idnot computed
Smooth char 0yes
Singular primes[]
Realization space: smooth over ℚnot computed
Realization space: smooth over ℤnot computed
Realization space: is regular schemenot computed
Realization space: singular fiber primesnot computed
Realization space: singular fiber characteristicsnot computed
Realization space: characteristic dimensionsnot computed
Realization space: characteristic dimension unexpectednot computed
Realization space: characteristic dimension variesnot computed

Other

Char poly splitsfalse
Simplicial arrangementno
Realization space: n qbar componentsnot computed

Tutte polynomial

\(T = x_{0}^{4} + 5 x_{0}^{3} + x_{0}^{2} x_{1} + 14 x_{0}^{2} + x_{0} x_{1}^{5} + 3 x_{0} x_{1}^{4} + 6 x_{0} x_{1}^{3} + 10 x_{0} x_{1}^{2} + 14 x_{0} x_{1}\)

Realization space

Ring\(\mathbb{Z}[x_{1}, x_{2}, x_{3}, x_{4}, x_{5}, x_{6}, x_{7}]\)
Defining ideal\(\left(0\right)\)
Inequations\(x_{4} x_{7} - x_{5} x_{6} \neq 0\), \(x_{5} - x_{7} \neq 0\), \(x_{4} x_{7} - x_{5} x_{6} + x_{5} - x_{7} \neq 0\), \(x_{4} - x_{6} \neq 0\), \(x_{1} x_{5} - x_{1} x_{7} + x_{4} x_{7} - x_{4} - x_{5} x_{6} + x_{6} \neq 0\), \(x_{2} x_{5} - x_{2} x_{7} - x_{3} x_{4} + x_{3} x_{6} + x_{4} x_{7} - x_{5} x_{6} \neq 0\), \(x_{2} x_{7} - x_{3} x_{6} \neq 0\), \(x_{3} - x_{7} \neq 0\), \(x_{2} x_{7} - x_{3} x_{6} + x_{3} - x_{7} \neq 0\), \(x_{2} - x_{6} \neq 0\), \(x_{1} x_{3} - x_{1} x_{7} + x_{2} x_{7} - x_{2} - x_{3} x_{6} + x_{6} \neq 0\), \(x_{1} x_{7} - x_{6} \neq 0\), \(x_{7} - 1 \neq 0\), \(x_{1} x_{7} - x_{6} - x_{7} + 1 \neq 0\), \(x_{1} - x_{6} \neq 0\), \(x_{6} \neq 0\), \(x_{6} - 1 \neq 0\), \(x_{7} \neq 0\), \(x_{2} x_{5} - x_{3} x_{4} \neq 0\), \(x_{3} - x_{5} \neq 0\), \(x_{2} x_{5} - x_{3} x_{4} + x_{3} - x_{5} \neq 0\), \(x_{2} - x_{4} \neq 0\), \(x_{1} x_{3} - x_{1} x_{5} + x_{2} x_{5} - x_{2} - x_{3} x_{4} + x_{4} \neq 0\), \(x_{1} x_{5} - x_{4} \neq 0\), \(x_{5} - 1 \neq 0\), \(x_{1} x_{5} - x_{4} - x_{5} + 1 \neq 0\), \(x_{1} - x_{4} \neq 0\), \(x_{4} \neq 0\), \(x_{4} - 1 \neq 0\), \(x_{5} \neq 0\), \(x_{1} x_{3} - x_{2} \neq 0\), \(x_{3} - 1 \neq 0\), \(x_{1} x_{3} - x_{2} - x_{3} + 1 \neq 0\), \(x_{1} - x_{2} \neq 0\), \(x_{2} \neq 0\), \(x_{2} - 1 \neq 0\), \(x_{3} \neq 0\), \(x_{1} \neq 0\), \(x_{1} - 1 \neq 0\)
Realization matrix\(\begin{pmatrix}1 & 0 & 1 & 0 & 1 & 1 & 1 & 1 & 0 \\ 0 & 1 & 1 & 0 & x_{1} & x_{2} & x_{4} & x_{6} & 0 \\ 0 & 0 & 0 & 1 & 1 & x_{3} & x_{5} & x_{7} & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1\end{pmatrix}\)

Combinatorics

Computed on the fly from the id.

Bases (55){1,2,4,9} {1,3,4,9} {2,3,4,9} {1,2,5,9} {1,3,5,9} {2,3,5,9} {1,4,5,9} {2,4,5,9} {3,4,5,9} {1,2,6,9} {1,3,6,9} {2,3,6,9} {1,4,6,9} {2,4,6,9} {3,4,6,9} {1,5,6,9} {2,5,6,9} {3,5,6,9} {4,5,6,9} {1,2,7,9} {1,3,7,9} {2,3,7,9} {1,4,7,9} {2,4,7,9} {3,4,7,9} {1,5,7,9} {2,5,7,9} {3,5,7,9} {4,5,7,9} {1,6,7,9} {2,6,7,9} {3,6,7,9} {4,6,7,9} {5,6,7,9} {1,2,8,9} {1,3,8,9} {2,3,8,9} {1,4,8,9} {2,4,8,9} {3,4,8,9} {1,5,8,9} {2,5,8,9} {3,5,8,9} {4,5,8,9} {1,6,8,9} {2,6,8,9} {3,6,8,9} {4,6,8,9} {5,6,8,9} {1,7,8,9} {2,7,8,9} {3,7,8,9} {4,7,8,9} {5,7,8,9} {6,7,8,9}
Non-bases (71){1,2,3,4} {1,2,3,5} {1,2,4,5} {1,3,4,5} {2,3,4,5} {1,2,3,6} {1,2,4,6} {1,3,4,6} {2,3,4,6} {1,2,5,6} {1,3,5,6} {2,3,5,6} {1,4,5,6} {2,4,5,6} {3,4,5,6} {1,2,3,7} {1,2,4,7} {1,3,4,7} {2,3,4,7} {1,2,5,7} {1,3,5,7} {2,3,5,7} {1,4,5,7} {2,4,5,7} {3,4,5,7} {1,2,6,7} {1,3,6,7} {2,3,6,7} {1,4,6,7} {2,4,6,7} {3,4,6,7} {1,5,6,7} {2,5,6,7} {3,5,6,7} {4,5,6,7} {1,2,3,8} {1,2,4,8} {1,3,4,8} {2,3,4,8} {1,2,5,8} {1,3,5,8} {2,3,5,8} {1,4,5,8} {2,4,5,8} {3,4,5,8} {1,2,6,8} {1,3,6,8} {2,3,6,8} {1,4,6,8} {2,4,6,8} {3,4,6,8} {1,5,6,8} {2,5,6,8} {3,5,6,8} {4,5,6,8} {1,2,7,8} {1,3,7,8} {2,3,7,8} {1,4,7,8} {2,4,7,8} {3,4,7,8} {1,5,7,8} {2,5,7,8} {3,5,7,8} {4,5,7,8} {1,6,7,8} {2,6,7,8} {3,6,7,8} {4,6,7,8} {5,6,7,8} {1,2,3,9}
Circuits (66){1,2,3} {1,2,4,5} {1,3,4,5} {2,3,4,5} {1,2,4,6} {1,3,4,6} {2,3,4,6} {1,2,5,6} {1,3,5,6} {2,3,5,6} {1,4,5,6} {2,4,5,6} {3,4,5,6} {1,2,4,7} {1,3,4,7} {2,3,4,7} {1,2,5,7} {1,3,5,7} {2,3,5,7} {1,4,5,7} {2,4,5,7} {3,4,5,7} {1,2,6,7} {1,3,6,7} {2,3,6,7} {1,4,6,7} {2,4,6,7} {3,4,6,7} {1,5,6,7} {2,5,6,7} {3,5,6,7} {4,5,6,7} {1,2,4,8} {1,3,4,8} {2,3,4,8} {1,2,5,8} {1,3,5,8} {2,3,5,8} {1,4,5,8} {2,4,5,8} {3,4,5,8} {1,2,6,8} {1,3,6,8} {2,3,6,8} {1,4,6,8} {2,4,6,8} {3,4,6,8} {1,5,6,8} {2,5,6,8} {3,5,6,8} {4,5,6,8} {1,2,7,8} {1,3,7,8} {2,3,7,8} {1,4,7,8} {2,4,7,8} {3,4,7,8} {1,5,7,8} {2,5,7,8} {3,5,7,8} {4,5,7,8} {1,6,7,8} {2,6,7,8} {3,6,7,8} {4,6,7,8} {5,6,7,8}
Flats by rank (72)
Hyperplanes (27){1,2,3,4,5,6,7,8} {1,2,3,9} {1,4,9} {2,4,9} {3,4,9} {1,5,9} {2,5,9} {3,5,9} {4,5,9} {1,6,9} {2,6,9} {3,6,9} {4,6,9} {5,6,9} {1,7,9} {2,7,9} {3,7,9} {4,7,9} {5,7,9} {6,7,9} {1,8,9} {2,8,9} {3,8,9} {4,8,9} {5,8,9} {6,8,9} {7,8,9}
Dual (rank 5)

Revlex encoding in this labeling (not canonicalized, so not linked): *******************************************************00000000000000000000000000000000000000000000000000000000000000000000000

Bases: {3,5,6,7,8} {2,5,6,7,8} {1,5,6,7,8} {3,4,6,7,8} {2,4,6,7,8} {1,4,6,7,8} {2,3,6,7,8} {1,3,6,7,8} {1,2,6,7,8} {3,4,5,7,8} {2,4,5,7,8} {1,4,5,7,8} {2,3,5,7,8} {1,3,5,7,8} {1,2,5,7,8} {2,3,4,7,8} {1,3,4,7,8} {1,2,4,7,8} {1,2,3,7,8} {3,4,5,6,8} {2,4,5,6,8} {1,4,5,6,8} {2,3,5,6,8} {1,3,5,6,8} {1,2,5,6,8} {2,3,4,6,8} {1,3,4,6,8} {1,2,4,6,8} {1,2,3,6,8} {2,3,4,5,8} {1,3,4,5,8} {1,2,4,5,8} {1,2,3,5,8} {1,2,3,4,8} {3,4,5,6,7} {2,4,5,6,7} {1,4,5,6,7} {2,3,5,6,7} {1,3,5,6,7} {1,2,5,6,7} {2,3,4,6,7} {1,3,4,6,7} {1,2,4,6,7} {1,2,3,6,7} {2,3,4,5,7} {1,3,4,5,7} {1,2,4,5,7} {1,2,3,5,7} {1,2,3,4,7} {2,3,4,5,6} {1,3,4,5,6} {1,2,4,5,6} {1,2,3,5,6} {1,2,3,4,6} {1,2,3,4,5}

Loops: none. Parallel classes of size > 1: none.

Downloads