Planar graphs

Planarization

In the mathematical field of graph theory, planarization is a method of extending graph drawing methods from planar graphs to graphs that are not planar, by embedding the non-planar graphs within a larger planar graph. Planarization may be performed by using any method to find a drawing (with crossings) for the given graph, and then replacing each crossing point by a new artificial vertex, causing each crossed edge to be subdivided into a path. The original graph will be represented as an immersion minor of its planarization. In incremental planarization, the planarization process is split into two stages. First, a large planar subgraph is found within the given graph. Then, the remaining edges that are not already part of this subgraph are added back one at a time, and routed through an embedding of the planar subgraph. When one of these edges crosses an already-embedded edge, the two edges that cross are replaced by two-edge paths, with a new artificial vertex that represents the crossing point placed at the middle of both paths. In some case a third local optimization stage is added to the planarization process, in which edges with many crossings are removed and re-added in an attempt to improve the planarization. (Wikipedia).

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Symmetrization

In this video, I define a cool operation called the symmetrization, which turns any matrix into a symmetric matrix. Along the way, I also explain how to show that an (abstract) linear transformation is one-to-one and onto. Finally, I show how to decompose and matrix in a nice way, sort of

From playlist Linear Transformations

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What are dilations

👉 Learn about dilations. Dilation is the transformation of a shape by a scale factor to produce an image that is similar to the original shape but is different in size from the original shape. A dilation that creates a larger image is called an enlargement or a stretch while a dilation tha

From playlist Transformations

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Linear Transformations: Onto

Linear Algebra: Continuing with function properties of linear transformations, we recall the definition of an onto function and give a rule for onto linear transformations.

From playlist MathDoctorBob: Linear Algebra I: From Linear Equations to Eigenspaces | CosmoLearning.org Mathematics

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What is an enlargement dilation

👉 Learn about dilations. Dilation is the transformation of a shape by a scale factor to produce an image that is similar to the original shape but is different in size from the original shape. A dilation that creates a larger image is called an enlargement or a stretch while a dilation tha

From playlist Transformations

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Linear Algebra for Computer Scientists. 7. Linear Combinations of Vectors

This computer science video is one of a series on linear algebra for computer scientists. In this video you will learn about linear combinations of vectors, that is, you will learn how to create new vectors by scaling then adding other vectors together. You will also learn that some sets

From playlist Linear Algebra for Computer Scientists

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Regularization 1

An introduction to regularization with weight decay.

From playlist Regularization

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Polarization of Light: circularly polarized, linearly polarized, unpolarized light.

3D animations explaining circularly polarized, linearly polarized, and unpolarized electromagnetic waves.

From playlist Physics

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What is a reduction dilation

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From playlist Transformations

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Which Complete Graphs are Planar? | Graph Theory

Which complete graphs are planar? Which complete graphs are nonplanar? We'll answer this question in today's graph theory lesson! We'll see that K1, K2, K3, and K4 are all planar complete graphs. Then, we'll prove that K5 is nonplanar and see why that implies no complete graph with at le

From playlist Graph Theory

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A Classification of Planar Graphs - A Proof of Kuratowski's Theorem

A visually explained proof of Kuratowski's theorem, an interesting, important and useful result classifying "planar" graphs. Proof adapted from: http://math.uchicago.edu/~may/REU2017/REUPapers/Xu,Yifan.pdf and: https://www.math.cmu.edu/~mradclif/teaching/228F16/Kuratowski.pdf Also check

From playlist Summer of Math Exposition Youtube Videos

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Lecture 22 - Planarity

This is Lecture 22 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%2022.pdf More information may

From playlist CSE547 - Discrete Mathematics - 1999 SBU

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Graph Theory: 61. Characterization of Planar Graphs

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From playlist Graph Theory part-10

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What are Planar Graphs? | Graph Theory

What are planar graphs? How can we draw them in the plane? In today's graph theory lesson we'll be defining planar graphs, plane graphs, regions of plane graphs, boundaries of regions of plane graphs, and introducing Euler's formula for connected plane graphs. A planar graph is a graph t

From playlist Graph Theory

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[Discrete Mathematics] Planar Graphs

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From playlist CMU 21-228 Discrete Mathematics

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From playlist Understanding Phased Array Systems and Beamforming

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Graph Theory: 60. Non Planar Graphs

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From playlist Graph Theory part-10

Related pages

Spanning tree | Graph theory | Dual graph | Graph minor | Local search (optimization) | Induced subgraph | Partial k-tree | Branch and cut | Path (graph theory) | Random permutation | Planar graph | Vertex (graph theory) | Glossary of graph theory | Embedding | Degree (graph theory) | SNP (complexity) | Parameterized complexity