dds/README.org
2020-11-28 23:26:03 +01:00

86 lines
3.8 KiB
Org Mode

* dds: A Home-made Toolkit for Discrete Dynamical Systems in Racket
This is a toolkit for playing with various discrete dynamical systems
in [[https://racket-lang.org/][Racket]]. A discrete dynamical system is a system which evolves from
a discrete state to some other discrete states (many or one). The
systems are discrete in the sense that we can identify successive
states with no other states in between. Equivalently, the phase state
of the system is discrete (and is often called the state graph).
These constraints imply the possibility of associating discrete,
possibly branching timelines to any evolution of the system.
*DISCLAIMER:* I develop this toolkit as a support for my research on
discrete dynamical systems. The primary objective for this framework
is to fit my approach to these systems. Essentially, this framework
should fit to the "shape of my mind", which is not necessarily the
same as yours.
Currently, the toolkit includes the following files:
- [[file:generic.rkt][generic.rkt]]: The generic interface for a discrete dynamical
system, with functions for constructing state graphs.
- [[file:utils.rkt][utils.rkt]]: Misc utility functions.
- [[file:networks.rkt][networks.rkt]]: Implements network-based models, which generalise
Boolean networks, threshold Boolean automata networks, multivalued
networks, etc.
- [[file:rs.rkt][rs.rkt]]: Implements reaction systems, a variant of set rewriting.
The toolkit is designed with Emacs [[https://orgmode.org/][Org-mode]] interoperability in mind.
The file [[file:example/example.org][example/example.org]] explains the features available for
interaction with Org-mode.
** Roadmap
Here is my current roadmap for this toolkit, in order. The first
element is what I am currently working on. The degree of certainty
that I work on the subsequent items decreases with their position
in the list.
*** TODO Start writing the docs properly with Scribble
Convert some of the comments to Scribble, in particular
module-level comments introducing the modules and each of
the sections.
Set up the infrastructure for extracting the in-source comments
using [[https://docs.racket-lang.org/scribble/srcdoc.html][this]].
*** TODO Think about /not/ using generics for the dynamics
Typed Racket can now type classes, and I can implement the idea
from the module =generics= as a class. However, I got this advice
on Racket Users group:
#+BEGIN_QUOTE
If you don't need to support arbitrary user implementations, you
can avoid generics and classes altogether and use structs whose
fields contain functions.
#+END_QUOTE
I will need to think about simpler implementations of the
interface to dynamics, which should also be simpler to type.
*** TODO Convert =dds= to Typed Racket
This will necessarily lead to updates in the comments, which
should be rewritten with Scribble.
I will do the conversion in the directory =typed/=, by
incrementally translating existing modules, definition
by definition.
The order I will convert the modules:
1. =utils=
2. =functions=
3. the module defining the interface to dynamics (currently =generics=)
4. =networks=
5. =rs=
*** TODO Split =networks= into general networks and threshold Boolean networks
*** TODO Submit =update-graph= to =stchang=
*** TODO Implement the BN \to RS conversion
*** TODO Implement the minimisation of TBF/SBF
*** TODO Contribute to Racket
- Make sequence-filter allow multivalued sequences, provided the
arity of the predicate is consistent with the arity of
the sequence.
- Add a sequence->hash function that accepts a multivalued
sequence of keys and values (exactly like what in-hash produces)
and copies them into a hash table.
*** TODO Test network inference with [[https://docs.racket-lang.org/racklog/index.html][Racklog]]