Classical studies : Seneca and Medea

More pictures, mainly for my own benefit. First, a possible refactoring of some bioclipse modules:

Where boxes are modules, and lines indicate dependencies. There's a lot of work in that arrow! Only the compute plugin and the seneca plugin have been ported (however incompletely) so far.

The second image shows the extension points for the putative CASE plugin. One is the judge extension point that already exists in the seneca plugin, and the other is a structure source:

This is more general than just a structure generator extension point, and could also include sources from files or databases. I think that this makes sense...

Comments

Egon Willighagen said…

MEDEA does not depend on CASE stuff; it's reaction functionality, oriented at mass spectrometry. However, MEDEA does provide MS spectrum prediction, and hence could be used in a CASE setup. So, MEDEA.case extends MEDEA, instead of MEDEA depending on CASE.

I don't understand why you would want to have MEDEA depend on CASE...

I think having a structure generator backed up by a database makes sense too.

1 October 2008 at 10:53

Adamantane, Diamantane, Twistane

After cubane, the thought occurred to look at other regular hydrocarbons. If only there was some sort of classification of chemicals that I could use look up similar structures. Oh wate, there is . Anyway, adamantane is not as regular as cubane, but it is highly symmetrical, looking like three cyclohexanes fused together. The vertices fall into two different types when colored by signature: The carbons with three carbon neighbours (degree-3, in the simple graph) have signature (a) and the degree-2 carbons have signature (b). Atoms of one type are only connected to atoms of another - the graph is bipartite . Adamantane connects together to form diamondoids (or, rather, this class have adamantane as a repeating subunit). One such is diamantane , which is no longer bipartite when colored by signature: It has three classes of vertex in the simple graph (a and b), as the set with degree-3 has been split in two. The tree for signature (c) is not shown. The graph is still bipartite accordin

Király's Method for Generating All Graphs from a Degree Sequence

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General Graph Layout : Putting the Parts Together

An essential tool for graph generation is surely the ability to draw graphs. There are, of course, many methods for doing so along with many implementations of them. This post describes one more (or perhaps an existing method - I haven't checked). Firstly, lets divide a graph up into two parts; a) the blocks, also known as ' biconnected components ', and b) trees connecting those blocks. This is illustrated in the following set of examples on 6 vertices: Trees are circled in green, and blocks in red; the vertices in the overlap between two circles are articulation points. Since all trees are planar, a graph need only have planar blocks to be planar overall. The layout then just needs to do a tree layout on the tree bits and some other layout on the embedding of the blocks. One slight wrinkle is shown by the last example in the image above. There are three parts - two blocks and a tree - just like the one to its left, but sharing a single articulation point. I had

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