86 lines
4.1 KiB
Org Mode
86 lines
4.1 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 utilities.
|
|
- [[file:functions.rkt][functions.rkt]]: Definitions for working with functions: tabulating,
|
|
constructing from tables, generating random functions, etc.
|
|
- [[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 Fix =ob-racket= to work with Typed Racket
|
|
Currently, the =ob-racket= backend for running Racket code blocks in
|
|
Org-mode assumes the code is written in =#lang racket=, which breaks
|
|
the output for tables for example. This makes the typed version of
|
|
=dds= essentially useless with tables.
|
|
|
|
*** TODO Fix [[file:example/example.org][example.org]]
|
|
I changed quite a number of things while converting =dds= to Typed
|
|
Racket, which should break a lot of things in [[file:example/example.org][example.org]].
|
|
|
|
*** TODO Think about splitting the library into lib and doc
|
|
*** TODO Implement string rewriting
|
|
*** TODO Implement [[https://en.wikipedia.org/wiki/P_system][P systems]]
|
|
*** TODO Consider splitting =dds/utils= into a separate package
|
|
*** TODO Implement a shorter syntax for defining Boolean functions
|
|
Right now, this is how one defines the Boolean function:
|
|
|
|
#+BEGIN_SRC racket :results output silent
|
|
(define (update-go st)
|
|
(auto-hash-ref/:
|
|
st
|
|
(or (and (not :Go) :new-x) (and :Go :old-x))))
|
|
#+END_SRC
|
|
|
|
It would be nice and probably not too difficult to implement
|
|
a macro allowing for a syntax like the following one:
|
|
#+BEGIN_SRC racket :results output silent
|
|
(define-pbf my-pbf (or (and (not :Go) :new-x) (and :Go :old-x)))
|
|
#+END_SRC
|
|
|
|
*** TODO Submit =update-graph= to =stchang=
|
|
*** TODO Implement =monotone?=
|
|
=monotone?= would verify whether a given Boolean function is
|
|
monotone according to the definition in the book /Boolean
|
|
Functions: Theory, Algorithms, and Applications/ by Crama
|
|
and Hammer.
|
|
|
|
*** TODO Consider optimizing the algorithms in =networks= and =dynamics=
|
|
*** 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]]
|