Graph Theory 101 (WebEngDus17)

Graph Theory 101 – putting theory into practice
Graphs are everywhere! Learn the core basics of graph theory and see how this can be applied in a number of practical, every-day use cases.

5min talk from ELI5 series (explain me like I'm five)
Presentation consists of slides and interactive flip-chart session (not uploaded here)

Transcript

1. Graph Theory 101 by @another_clue
   putting theory into practice
   

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2. graph theory
   discrete mathematics
   2
   

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3. No, not charts/diagrams!
   3
   

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4. G=(V,E)
   ordered set G = (V,E)
   V: set of vertices/nodes/points
   E: set of edges/connections/lines/arrows/arcs
   4
   

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5. properties
   empty
   trivial
   edgeless
   … 5
   

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6. attributes
   vertex labels
   edge weights
   types
   … 6
   

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7. putting into Practice
   7
   

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8. Facebook
   8
   

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9. Facebook
   V = people
   E = friends (undirected)
   Amy befriended with Bob
   9
   

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10. Facebook
    is an undirected graph
    10
    

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11. Twitter
    11
    

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12. Twitter
    V = accounts
    E = follower (directed)
    YourName follows @webengdus
    12
    

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13. Twitter
    is a digraph (directed graph)
    13
    

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14. git
    14
    

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15. git
    V = objects (commits, tags etc.)
    E = object references
    v1.0.0 refs #abc
    15
    

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16. git
    is a DAG (directed acyclic graph)
    16
    

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17. sat nav
    17
    

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18. sat nav
    V = cities
    E = roads (weight=distance)
    All roads lead to Rome?
    18
    

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19. sat nav
    multigraph (parallel edges, loops)
    shortest path? algorithms and heuristics
    19
    

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20. Conclusions
    20
    

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21. graphs are everywhere!
    21
    

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22. care about edges? use a graph!
    22
    

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23. graph libraries readily available
    23
    

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24. plenty of graph databases
    24
    

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25. Do you need a graph database?
    25
    

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26. // thank you!
    26
    @another_clue – https://lueck.tv/
    

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27. 27
    Exercise
    

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28. 28
    @WebEngDus
    Exercise
    

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29. 29
    @another_clue
    @WebEngDus
    Exercise
    

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30. 30
    @clue
    @another_clue
    @WebEngDus
    Exercise
    

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31. 31
    @clue
    @another_clue
    @WebEngDus
    @graphp
    Exercise
    

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32. 32
    @clue
    @another_clue
    @WebEngDus
    @graphp
    YOU!
    Exercise
    

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33. More…
    33
    

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34. static analysis
    34
    

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35. static analysis
    V = functions
    E = functions invocation
    main() calls run() calls print()
    35
    

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36. static analysis
    digraph
    remove vertices with indegree=0
    36
    

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