MST. Given connected graph G with positive edge weights, find a min weight set of edges that connects all of the vertices.
Minimum Spanning Tree
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introduction
Weighted graph API cycles and cuts
Kruskal’s algorithm
Prim’s algorithm advanced algorithms clustering 11
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References: Algorithms in Java (Part 5), Chapter 20
Intro to Algs and Data Structures, Section 5.4
Copyright © 2007 by Robert Sedgewick and Kevin Wayne.
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Minimum Spanning Tree
MST. Given connected graph G with positive edge weights, find a min weight set of edges that connects all of the vertices.
24
4
introduction weighted graph API cycles and cuts
Kruskal’s algorithm
Prim’s algorithm advanced algorithms clustering 23
6
9
18
5
11
16
8
10
14
7
21
cost(T) = 50
Brute force: Try all possible spanning trees problem 1: not so easy to implement problem 2: far too many of them
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Ex: [Cayley, 1889]: VV-2 spanning trees on the complete graph on V vertices.
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MST Origin
Medical Image Processing
Otakar Boruvka (1926).
Electrical Power Company of Western Moravia in Brno.
Most economical construction of electrical power network.
Concrete engineering problem is now a cornerstone problem in combinatorial optimization.
MST describes arrangement of nuclei in the epithelium for cancer research
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Otakar Boruvka
http://www.bccrc.ca/ci/ta01_archlevel.html
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Applications
MST is fundamental problem with diverse applications.
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Network design.
– telephone, electrical, hydraulic, TV cable, computer, road
Approximation algorithms for NP-hard problems.
– traveling salesperson problem, Steiner tree
Indirect applications.
– max bottleneck paths
– LDPC codes for error correction
– image registration with Renyi entropy
– learning salient features for
References: ! Ex: [Cayley, 1889]: VV-2 spanning trees on the complete graph on V vertices. Otakar Boruvka (1926).