Tag Archives: directed graphs

Reality has Levels

It’s been a while since I blogged. I’ve been busy.

A major theme emerging from ‘writing my book’ is that we humans are very bad at confusing our models of reality with the reality we are modelling.

I started planning with the ‘Freemind mind-mapping tool for hierarchical brains’ before finding my own creative process had a network architecture and discovering ‘concept mapping’ which uses graphs to represent concepts and propositions. I saw that graphs were what I needed and decided to experiment with building my own software tools from bits I had lying around.

I didn’t have a current programming language, so I set out to learn Clojure. Being a Lisp, Clojure uses tree-structures internally to represent lists and extends the idea to abstractions such as collections but the only native data structures available to me appeared to be 1-dimensional.  I confidently expected to be able to find ways to extend this to 3 or more dimensional graphs but despite much reading and learning lots of other things, I’d failed to find what I was looking for. I had in mind the kind of structures you can build with pointers, in languages like ‘C’. There are graph libraries but I was too new to Clojure to believe my first serious program needed to be dependent on language extensions, when I haven’t securely grasped the basics.

This morning, I think I ‘got it’. I am trying to build a computational model of my graphical view of a mathematical idea which models a cognitive model of reality. There was always scope for confusion. Graphs aren’t really a picture, they are a set of 1-dimensional connections and potentially another set of potential views of those connections, constructed for a particular purpose. I was trying to build a data structure of a view of a graph, not the graph itself and that was a really bad idea. At least I didn’t get software confused with ‘actual’ reality, so there’s still hope for me.

Yesterday, I used Clojure/Leiningen’s in-built Test-Driven Development tool for the first time. It looks great. The functional model makes TDD simple.

The British Computing Society

I just engaged in a debate about the BCS on LinkedIn . Yes, THAT again: https://andywootton.wordpress.com/2013/11/08/is-it-whats-in-a-name/

Officially, the three letters B, C and S, don’t stand for anything. They used to mean British Computer Society and that is what it still says on the Royal Charter that bestows upon the BCS the royal privilege of awarding Chartered status to members. I’ve suggested we get out the correcting fluid (or an appropriately skilled scribe) and change the middle word to “Computing”.

In his famous book title, Niklaus Wirth said, “Algorithms + Data Structures = Programs”
https://en.wikipedia.org/wiki/Algorithms_%2B_Data_Structures_%3D_Programs

My suggestion was that ‘Computing + Information = what BCS members do’

Look what Wiki-P says about the word “computing”: https://en.wikipedia.org/wiki/Computing

“Computing is any goal-oriented activity requiring, benefiting from, or creating algorithmic processes—e.g. through computers. Computing includes designing, developing and building hardware and software systems; processing, structuring, and managing various kinds of information; doing scientific research on and with computers; making computer systems behave intelligently; and creating and using communications and entertainment media. The field of computing includes computer engineering, software engineering, computer science, information systems, and information technology.”

At the moment, the ambitions of BCS Council only extend as far as the ‘IT’, which comes last in the list. Some of us “software engineers, computer scientists and information systems” people feel we are not being adequately represented. I promise I didn’t change Wikipedia to prove my case.

There aren’t many things in informatics (the Anglicised version of what the rest of Europe call ‘computing + information’) that can’t be represented by a ‘directed graph’.
https://en.wikipedia.org/wiki/Directed_graph#/media/File:Directed.svg

The ‘blobs’ normally show the ‘processes’ where the computing happens (people or machines) or ‘information at rest’, typically with a different colour or blob-shape. The ‘arcs’ or ‘edges’ typically show potential ‘flows of information’ or ‘control’. It is an unfortunate coincidence that the directed graph example I found shows us going around in circles.