Matroid 3.8.31
| Label | 3.8.31 |
|---|---|
| Id | r3_n8_0******0******0***0******0*0**0************************* |
| Rank | 3 |
| n | 8 |
Basic invariants
Representability
| Characteristic set | exactly characteristic 2 [2] |
|---|---|
| Realizable | yes |
| Realizable char0 | no |
| Regular | no |
| Binary | no |
| Ternary | no |
| Quaternary | no |
| Graphic | no |
Realization space
| Status | computed_realization_space |
|---|---|
| Dimension of realization space | -1 |
| Expected dimension over ℤ | 2 |
| Components of realization space | 0 |
| Free realization space | no |
| Principal ideal | yes |
| Birational type | empty how determined: birational type method: empty_char0 |
| Birational type components | show[] |
| Good basis | 1,2,4 |
| Good basis v2 | 1,2,4 |
Geometry
| Realization space: scheme simple core id | r3_n8_0******0******0***0******0*0**0************************* |
|---|---|
| Smooth char 0 | yes |
| Singular primes | [] |
| Realization space: smooth over ℚ | not computed |
| Realization space: smooth over ℤ | no how determined: smoothness method: nonflat_vertical |
| Realization space: is regular scheme | yes how determined: regularity method: three_lines_deletion regularity witness: 8=>r3_n7_0******0******0***0******0*0**0**** |
| Realization space: singular fiber primes | [] how determined: singular fiber primes method: smooth_deletion_empty_target |
| Realization space: singular fiber characteristics | not computed |
| Realization space: characteristic dimensions | show[
{
"p": 2,
"d": 2
}
]how determined: characteristic dimensions method: finite_exact_fiber_saturation |
| Realization space: characteristic dimension unexpected | yes |
| Realization space: characteristic dimension varies | no |
Other
| Char poly splits | false |
|---|---|
| Simplicial arrangement | no |
| Realization space: n qbar components | 0 |
Tutte polynomial
\(T = x_{0}^{3} + 5 x_{0}^{2} + 7 x_{0} x_{1} + 8 x_{0} + x_{1}^{5} + 3 x_{1}^{4} + 6 x_{1}^{3} + 10 x_{1}^{2} + 8 x_{1}\)
Realization space
| Ring | \(\mathbb{Z}[x_{1}, x_{2}]\) |
|---|---|
| Defining ideal | \(\left(2\right)\) |
| Inequations | \(x_{1} - x_{2} \neq 0\), \(x_{2} - 1 \neq 0\), \(x_{1} - 1 \neq 0\), \(x_{1} + x_{2} - 2 \neq 0\), \(x_{1} + x_{2} \neq 0\), \(x_{1} + x_{2} - 1 \neq 0\), \(x_{1} \neq 0\), \(x_{2} \neq 0\) |
| Realization matrix | \(\begin{pmatrix}1 & 0 & 1 & 0 & 1 & 0 & 1 & 1 \\ 0 & 1 & 1 & 0 & 0 & 1 & 1 & x_{1} \\ 0 & 0 & 0 & 1 & 1 & -1 & 1 & x_{2}\end{pmatrix}\) |
Combinatorics
Computed on the fly from the id.
Bases (49)
{1,2,4} {1,3,4} {2,3,4} {1,2,5} {1,3,5} {2,3,5} {2,4,5} {3,4,5} {1,2,6} {1,3,6} {2,3,6} {1,4,6} {3,4,6} {1,5,6} {2,5,6} {4,5,6} {1,2,7} {1,3,7} {2,3,7} {1,4,7} {2,4,7} {1,5,7} {3,5,7} {4,5,7} {2,6,7} {3,6,7} {4,6,7} {5,6,7} {1,2,8} {1,3,8} {2,3,8} {1,4,8} {2,4,8} {3,4,8} {1,5,8} {2,5,8} {3,5,8} {4,5,8} {1,6,8} {2,6,8} {3,6,8} {4,6,8} {5,6,8} {1,7,8} {2,7,8} {3,7,8} {4,7,8} {5,7,8} {6,7,8}Non-bases (7)
{1,2,3} {1,4,5} {2,4,6} {3,5,6} {3,4,7} {2,5,7} {1,6,7}Circuits (42)
{1,2,3} {1,4,5} {2,3,4,5} {2,4,6} {1,3,4,6} {1,2,5,6} {3,5,6} {1,2,4,7} {3,4,7} {2,5,7} {1,3,5,7} {1,6,7} {2,3,6,7} {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} {2,4,5,8} {3,4,5,8} {1,2,6,8} {1,3,6,8} {2,3,6,8} {1,4,6,8} {3,4,6,8} {1,5,6,8} {2,5,6,8} {4,5,6,8} {1,2,7,8} {1,3,7,8} {2,3,7,8} {1,4,7,8} {2,4,7,8} {1,5,7,8} {3,5,7,8} {4,5,7,8} {2,6,7,8} {3,6,7,8} {4,6,7,8} {5,6,7,8}Flats by rank (24)
- rank 0 (1): {}
- rank 1 (8): {1} {2} {3} {4} {5} {6} {7} {8}
- rank 2 (14): {1,2,3} {1,4,5} {2,4,6} {3,5,6} {3,4,7} {2,5,7} {1,6,7} {1,8} {2,8} {3,8} {4,8} {5,8} {6,8} {7,8}
- rank 3 (1): {1,2,3,4,5,6,7,8}
Hyperplanes (14)
{1,2,3} {1,4,5} {2,4,6} {3,5,6} {3,4,7} {2,5,7} {1,6,7} {1,8} {2,8} {3,8} {4,8} {5,8} {6,8} {7,8}Lines (7)
{1,2,3} {1,4,5} {2,4,6} {3,5,6} {3,4,7} {2,5,7} {1,6,7}Dual (rank 5)
Revlex encoding in this labeling (not canonicalized, so not linked): *************************0**0*0******0***0******0******0
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} {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} {1,2,5,7,8} {2,3,4,7,8} {1,3,4,7,8} {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} {2,3,4,6,8} {1,2,4,6,8} {1,2,3,6,8} {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
- Record as JSON
- OSCAR:
matroid_from_revlex_basis_encoding("0******0******0***0******0*0**0*************************", 3, 8)