Graph connectivity | Combinatorial optimization

Cut (graph theory)

In graph theory, a cut is a partition of the vertices of a graph into two disjoint subsets. Any cut determines a cut-set, the set of edges that have one endpoint in each subset of the partition. These edges are said to cross the cut. In a connected graph, each cut-set determines a unique cut, and in some cases cuts are identified with their cut-sets rather than with their vertex partitions. In a flow network, an s–t cut is a cut that requires the source and the sink to be in different subsets, and its cut-set only consists of edges going from the source's side to the sink's side. The capacity of an s–t cut is defined as the sum of the capacity of each edge in the cut-set. (Wikipedia).

Cut (graph theory)
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Graph Theory: 53. Cut-Vertices

Here we introduce the term cut-vertex and show a few examples where we find the cut-vertices of graphs. We then go through a proof of a characterisation of cut-vertices: a vertex v is a cut-vertex if and only if there exist vertices u and w (distinct from v) such that v lies on every u-w

From playlist Graph Theory part-9

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Vertex Cuts in Graphs (and a bit on Connectivity) | Graph Theory, Vertex-Connectivity

What is a vertex cut of a graph? And how can we use vertex cuts to describe how connected a graph is? We have discussed cut vertices and connected graphs before, but by tying them together in a way, we are able to characterize different levels of connectivity in graphs. The focus of this l

From playlist Graph Theory

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Graph Theory: 02. Definition of a Graph

In this video we formally define what a graph is in Graph Theory and explain the concept with an example. In this introductory video, no previous knowledge of Graph Theory will be assumed. --An introduction to Graph Theory by Dr. Sarada Herke. This video is a remake of the "02. Definitio

From playlist Graph Theory part-1

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Cutting Metal Pieces in Graph Theory

Applying the onion skin algorithm to create an Eulerian Circuit and cut metal into a specified number of pieces

From playlist Graph Theory

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Graph Theory FAQs: 01. More General Graph Definition

In video 02: Definition of a Graph, we defined a (simple) graph as a set of vertices together with a set of edges where the edges are 2-subsets of the vertex set. Notice that this definition does not allow for multiple edges or loops. In general on this channel, we have been discussing o

From playlist Graph Theory FAQs

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Edge Cuts and Edge Connectivity | Graph Theory

Edge cuts, minimum edge cuts, minimal edge cuts, and edge connectivity are all introduced in today's graph theory lesson! Edge cuts are similar to vertex cuts but, of course, with edges! An edge cut of a nontrivial graph G is a set, X, of edges of G, such that G-X is disconnected. The car

From playlist Graph Theory

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What is a Graph? | Graph Theory

What is a graph? A graph theory graph, in particular, is the subject of discussion today. In graph theory, a graph is an ordered pair consisting of a vertex set, then an edge set. Graphs are often represented as diagrams, with dots representing vertices, and lines representing edges. Each

From playlist Graph Theory

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Graph Theory: 36. Definition of a Tree

In this video I define a tree and a forest in graph theory. I discuss the difference between labelled trees and non-isomorphic trees. I also show why every tree must have at least two leaves. An introduction to Graph Theory by Dr. Sarada Herke. Related Videos: http://youtu.be/zxu0dL436gI

From playlist Graph Theory part-7

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Lecture 19 - Degree Sequences & Invariants

This is Lecture 19 of the CSE547 (Discrete Mathematics) taught by Professor Steven Skiena [http://www.cs.sunysb.edu/~skiena/] at Stony Brook University in 1999. The lecture slides are available at: http://www.cs.sunysb.edu/~algorith/math-video/slides/Lecture%2019.pdf More information may

From playlist CSE547 - Discrete Mathematics - 1999 SBU

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What are Connected Graphs? | Graph Theory

What is a connected graph in graph theory? That is the subject of today's math lesson! A connected graph is a graph in which every pair of vertices is connected, which means there exists a path in the graph with those vertices as endpoints. We can think of it this way: if, by traveling acr

From playlist Graph Theory

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Adventures in Perturbation Theory by Jake Bourjaily

PROGRAM RECENT DEVELOPMENTS IN S-MATRIX THEORY (ONLINE) ORGANIZERS: Alok Laddha, Song He and Yu-tin Huang DATE: 20 July 2020 to 31 July 2020 VENUE:Online Due to the ongoing COVID-19 pandemic, the original program has been canceled. However, the meeting will be conducted through online

From playlist Recent Developments in S-matrix Theory (Online)

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15. Graph limits II: regularity and counting

MIT 18.217 Graph Theory and Additive Combinatorics, Fall 2019 Instructor: Yufei Zhao View the complete course: https://ocw.mit.edu/18-217F19 YouTube Playlist: https://www.youtube.com/playlist?list=PLUl4u3cNGP62qauV_CpT1zKaGG_Vj5igX Prof. Zhao explains how graph limits can be used to gener

From playlist MIT 18.217 Graph Theory and Additive Combinatorics, Fall 2019

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Hamiltonian Cycles, Graphs, and Paths | Hamilton Cycles, Graph Theory

What are Hamiltonian cycles, graphs, and paths? Also sometimes called Hamilton cycles, Hamilton graphs, and Hamilton paths, we’ll be going over all of these topics in today’s video graph theory lesson! A Hamilton cycle in a graph G is a cycle containing all vertices of G. A Hamilton path

From playlist Graph Theory

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Clustering and classification from the core to the edge - Thomas Strohmer, California University

This workshop - organised under the auspices of the Isaac Newton Institute on “Approximation, sampling and compression in data science” — brings together leading researchers in the general fields of mathematics, statistics, computer science and engineering. About the event The workshop ai

From playlist Mathematics of data: Structured representations for sensing, approximation and learning

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Subtracting a Vertex from a Graph (Vertex Deletion) | Graph Theory

How do we subtract a vertex from a graph? This is also sometimes referred to as deleting a vertex from a graph. So call it vertex subtraction or vertex deletion, whichever you please, that’s what we are going over today! Deleting a vertex from a graph is pretty intuitive. First we just re

From playlist Graph Theory

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The Definition of a Graph (Graph Theory)

The Definition of a Graph (Graph Theory) mathispower4u.com

From playlist Graph Theory (Discrete Math)

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What are Vertex Separating Sets? | Graph Theory

What are vertex separating sets in graph theory? We'll be going over the definition of a vertex separating set and some examples in today's video graph theory lesson! Let G be a graph and S be a vertex cut of G. As in, S is a set of vertices of G such that G - S is disconnected. Then, let

From playlist Set Theory

Related pages

Graph (discrete mathematics) | Connectivity (graph theory) | Vector space | Finite field | Karp's 21 NP-complete problems | Glossary of graph theory | Semidefinite programming | Vertex separator | Cycle space | Gomory–Hu tree | Max-flow min-cut theorem | Tree (graph theory) | Graph theory | Cycle graph | Bipartite graph | Vertex (graph theory) | Partition of a set | Symmetric difference | Edmonds–Karp algorithm | Split (graph theory) | Graph cuts in computer vision | Flow network | Basis (linear algebra) | Bridge (graph theory) | Linear programming | Orthogonal complement