Difference between revisions of "MCSN Thursday, 15-Sep-11"
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| − | + | = Today's assignment = | |
| + | Read sections 1.3.3 to 1.5; submit 1.6; come to class prepared with a Pajek example drawn from the Web, and illustrating chapter content. This will be a regular Thursday assignment. This week, the ESNAP readings focussed on a directed graph, so any directed graph from the web is fine. For instance, you could extract a portion of Twitter.com "following" relations, or look at musician relations (influences, influenced by) on allmusic.com. The point is to create a directed graph in Pajek. | ||
| + | = Question of the day = | ||
| + | |||
| + | * Definition: Combinatorics: counting the number of structures with particular properties. (e.g. the number of different connected, undirected, simple graphs on 4 vertices) | ||
| + | * Definition: "Different": non-isomorphic | ||
| + | ** Here, "different" means "non-isomorphic". | ||
| + | ** Isomorphic graphs contain the same connection information | ||
| + | ** E.g.: a square and a trapazoid and a twisted square graph are all isomorphic | ||
| + | ** Energizing graphs in Pajek always generates an isomorphic equivalent | ||
| + | |||
| + | |||
| + | * '''Question: What is the relevance of graph combinatorics to the cross-cultural study of musical groups? What might be revealed by an investigate of the relation between non-isomorphic graph types, and the dynamics of performance?''' | ||
| + | |||
| + | = Brainstorming continues...= | ||
* More precipitation from your [[Brainstorming MCSN | brainstorms]] | * More precipitation from your [[Brainstorming MCSN | brainstorms]] | ||
| − | + | ||
| − | + | = Homework exercises from Tuesday - review = | |
| − | * | + | |
| − | + | = Nuts-and-bolts: how to create networks in Pajek = | |
| − | + | * Creating and manipulating networks in Pajek itself | |
| − | + | * Editing Pajek files in a text processor | |
| − | + | ** Edge and arc list formats | |
| + | ** Matrix format | ||
| + | * Using [http://pajek.imfm.si/doku.php?id=faq:text2pajek txt2pajek] | ||
| + | * Using a programming language (e.g. scripting language such as php, perl, etc.) to generate Pajek files | ||
| + | |||
* More combinatorics... | * More combinatorics... | ||
** How many lines does a complete simple graph on n vertices contain? | ** How many lines does a complete simple graph on n vertices contain? | ||
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*** Directed graphs | *** Directed graphs | ||
** How many different undirected simple graphs are there on n vertices? | ** How many different undirected simple graphs are there on n vertices? | ||
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*** Counting: | *** Counting: | ||
**** [http://mapleta.maths.uwa.edu.au/~gordon/remote/graphs/index.html#nums numbers] | **** [http://mapleta.maths.uwa.edu.au/~gordon/remote/graphs/index.html#nums numbers] | ||
**** [http://gfredericks.com/sandbox/graphs/browse pictures] | **** [http://gfredericks.com/sandbox/graphs/browse pictures] | ||
Revision as of 06:37, 15 September 2011
Contents
Today's assignment
Read sections 1.3.3 to 1.5; submit 1.6; come to class prepared with a Pajek example drawn from the Web, and illustrating chapter content. This will be a regular Thursday assignment. This week, the ESNAP readings focussed on a directed graph, so any directed graph from the web is fine. For instance, you could extract a portion of Twitter.com "following" relations, or look at musician relations (influences, influenced by) on allmusic.com. The point is to create a directed graph in Pajek.
Question of the day
- Definition: Combinatorics: counting the number of structures with particular properties. (e.g. the number of different connected, undirected, simple graphs on 4 vertices)
- Definition: "Different": non-isomorphic
- Here, "different" means "non-isomorphic".
- Isomorphic graphs contain the same connection information
- E.g.: a square and a trapazoid and a twisted square graph are all isomorphic
- Energizing graphs in Pajek always generates an isomorphic equivalent
- Question: What is the relevance of graph combinatorics to the cross-cultural study of musical groups? What might be revealed by an investigate of the relation between non-isomorphic graph types, and the dynamics of performance?
Brainstorming continues...
- More precipitation from your brainstorms
Homework exercises from Tuesday - review
Nuts-and-bolts: how to create networks in Pajek
- Creating and manipulating networks in Pajek itself
- Editing Pajek files in a text processor
- Edge and arc list formats
- Matrix format
- Using txt2pajek
- Using a programming language (e.g. scripting language such as php, perl, etc.) to generate Pajek files
