Duality theories | Matroid theory

Dual matroid

In matroid theory, the dual of a matroid is another matroid that has the same elements as , and in which a set is independent if and only if has a basis set disjoint from it. Matroid duals go back to the original paper by Hassler Whitney defining matroids. They generalize to matroids the notions of plane graph duality. (Wikipedia).

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Duality Argument

In this video, I present a very classical example of a duality argument: Namely, I show that T^T is one-to-one if and only if T is onto and use that to show that T is one-to-one if and only if T^T is onto. This illustrates the beautiful interplay between a vector space and its dual space,

From playlist Dual Spaces

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Dual basis

Dual basis definition and proof that it's a basis In this video, given a basis beta of a vector space V, I define the dual basis beta* of V*, and show that it's indeed a basis. We'll see many more applications of this concept later on, but this video already shows that it's straightforwar

From playlist Dual Spaces

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MATLAB Basics: Get The Most Out of MATLAB

In this livestream, Heather Gorr and Elsie Eigerman will be walking through the fundamentals of programming with MATLAB. This isn’t just for beginners; we’ll show you the latest and greatest tips and tricks to help you get the most out of MATLAB. We’ll also walk-through core concepts for t

From playlist MATLAB and Simulink Livestreams

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Dual Basis Example

In this video, I show how to explicitly calculate dual bases. More specifically, I find the dual basis corresponding to the basis (2,1) and (3,1) of R^2. Hopefully this will give you a better idea of how dual bases work. Subscribe to my channel: https://www.youtube.com/c/drpeyam What is

From playlist Dual Spaces

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Joseph Bonin: Delta-matroids as subsystems of sequences of Higgs lifts

Abstract: Delta-matroids generalize matroids. In a delta-matroid, the counterparts of bases, which are called feasible sets, can have different sizes, but they satisfy a similar exchange property in which symmetric differences replace set differences. One way to get a delta-matroid is to t

From playlist Combinatorics

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Every basis is a dual basis

In this video, I show a very neat result about dual spaces: Namely, any basis of V* is automatically a dual basis of some basis of V. Even though this result is very interesting, it's the proof that makes this very exciting, by simply using the fact that V and V** are 'very' isomorphic. En

From playlist Dual Spaces

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How to Use Base and Model Workspaces

Learn about what base and model workspaces are, how to create variables in two workspaces, and the differences between the two workspaces. Check out the full playlist, which shows how to use MATLAB® and Simulink® across a range of topics: https://youtube.com/playlist?list=PLn8PRpmsu08oBSj

From playlist “How To” with MATLAB and Simulink

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MATLAB tutorial: Functions of multiple arguments

Get a Free Trial: https://goo.gl/C2Y9A5 Get Pricing Info: https://goo.gl/kDvGHt Ready to Buy: https://goo.gl/vsIeA5 http://blogs.mathworks.com/videos This MATLAB tutorial deals with functions of more than one input or output.

From playlist MATLAB Video tutorial blog

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Yusuke Kobayashi: A weighted linear matroid parity algorithm

The lecture was held within the framework of the follow-up workshop to the Hausdorff Trimester Program: Combinatorial Optimization. Abstract: The matroid parity (or matroid matching) problem, introduced as a common generalization of matching and matroid intersection problems, is so gener

From playlist Follow-Up-Workshop "Combinatorial Optimization"

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Connecting tropical intersection theory with polytope algebra in types A and B by Alex Fink

PROGRAM COMBINATORIAL ALGEBRAIC GEOMETRY: TROPICAL AND REAL (HYBRID) ORGANIZERS Arvind Ayyer (IISc, India), Madhusudan Manjunath (IITB, India) and Pranav Pandit (ICTS-TIFR, India) DATE & TIME: 27 June 2022 to 08 July 2022 VENUE: Madhava Lecture Hall and Online Algebraic geometry is t

From playlist Combinatorial Algebraic Geometry: Tropical and Real (HYBRID)

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Anna De Mier: Approximating clutters with matroids

Abstract: There are several clutters (antichains of sets) that can be associated with a matroid, as the clutter of circuits, the clutter of bases or the clutter of hyperplanes. We study the following question: given an arbitrary clutter Λ, which are the matroidal clutters that are closest

From playlist Combinatorics

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Determining if a set of points makes a parallelogram or not

👉 Learn how to determine the figure given four points. A quadrilateral is a polygon with four sides. Some of the types of quadrilaterals are: parallelogram, square, rectangle, rhombus, kite, trapezoid, etc. Each of the types of quadrilateral has its properties. Given four points that repr

From playlist Quadrilaterals on a Coordinate Plane

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Gary Gordon and Liz McMahon: Generalizations of Crapo's Beta Invariant

Abstract: Crapo's beta invariant was defined by Henry Crapo in the 1960s. For a matroid M, the invariant β(M) is the non-negative integer that is the coefficient of the x term of the Tutte polynomial. Crapo proved that β(M) is greater than 0 if and only if M is connected and M is not a loo

From playlist Combinatorics

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András Frank: Non TDI Optimization with Supermodular Functions

The notion of total dual integrality proved decisive in combinatorial optimization since it properly captured a phenomenon behind the tractability of weighted optimization problems. For example, we are able to solve not only the maximum cardinality matching (degree-constrained subdigraph,

From playlist HIM Lectures 2015

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Kevin Hendrey - Obstructions to bounded branch-depth in matroids (CMSA Combinatorics Seminar)

Kevin Hendrey (Institute for Basic Science) presents “Obstructions to bounded branch-depth in matroids”, 24 November 2020 (CMSA Combinatorics Seminar).

From playlist CMSA Combinatorics Seminar

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Nonlinear algebra, Lecture 13: "Polytopes and Matroids ", by Mateusz Michalek

This is the thirteenth lecture in the IMPRS Ringvorlesung, the advanced graduate course at the Max Planck Institute for Mathematics in the Sciences.

From playlist IMPRS Ringvorlesung - Introduction to Nonlinear Algebra

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What are Disjoint Sets? | Set Theory

What are disjoint sets? That is the topic of discussion in today's lesson! Two sets, A and B, are disjoint if and only if A intersect B is equal to the empty set. This means that two sets are disjoint if and only if they have no elements in common. This is the same as the two sets being "m

From playlist Set Theory

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Victor Chepoi: Simple connectivity, local to global, and matroids

Victor Chepoi: Simple connectivity, local-to-global, and matroids A basis graph of a matroid M is the graph G(M) having the bases of M as the vertex-set and the pairs of bases differing by an elementary exchange as edges. Basis graphs of matroids have been characterized by S.B. Maurer, J.

From playlist HIM Lectures 2015

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Gyula Pap: Linear matroid matching in the oracle model

Gyula Pap: Linear matroid matching in the oracle model Linear matroid matching is understood as a special case of matroid matching when the matroid is given with a matrix representation. However, for certain examples of linear matroids, the matrix representation is not given, and actuall

From playlist HIM Lectures 2015

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MATLAB Online Server – Host MATLAB Online on Your Infrastructure

MATLAB Online Server™ lets you host MATLAB Online™ on-premises or on your cloud environment. It integrates with your existing network file system and authentication services to provide an experience that you can fully manage and control. For MATLAB® users, MATLAB Online provides instant ac

From playlist Modeling and Simulation | Developer Tech Showcase

Related pages

Dual graph | Matroid rank | Vector space | Algebraic matroid | Hassler Whitney | Uniform matroid | Binary matroid | Graphic matroid | Complement (set theory) | GF(2) | Partition matroid | Eulerian matroid | Gammoid | Involution (mathematics) | Matroid minor | Regular matroid | Matroid oracle | Bipartite matroid | Dual polyhedron | Orthogonal complement