Symbolic analysis

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Revision as of 18:13, 12 December 2009 by Erkki Laitila (talk | contribs)

Symbolic analysis is a method for making interpretations based on symbols. Traffic as symbolic Processing.jpg.

In figure there is an object to be monitored using a traffic light. That symbol is a signal to our eyes to activate an interpretation: to wait (red light), to be alert(yellow), or to go (green) ahead. In our brains there is a formal logic to handle interpretations from traffic lights. We suggest that our brains work like an automaton in traffic lights. Sometimes, when we are in a hurry, we ask questiong from ourselves: can we now go, can we now go... A detection from a traffic light causes a condition to be checked in the logic. It gives us the answer: You should wait, you should wait... Now you can go. That kind of symbol (traffic light) gives us pragmatic value, because it makes our travel safe, but still we can flexibly go further to home, work, trip etc - even when the traffic is very heavy.

That was the main principle of symbolic analysis in a nutshell.

Possible Uses for Symbolic Analysis

Symbolic Analysis written in Visual Prolog can be used in modeling typical formal systems, which meet requirements for atomisticity: formal languages, theorem provers, many mathematical packages, as well as simulation and optimization packages, where the type system has been written using Vip domains.

Obs. In PDC Prolog there are numerous examples of Prolog domains written for


Implementing a Symbol and Interpretation

Symbol is a reserved word in Visual Prolog, therefore we use the object SymbolicElement to model any Symbol.


clauses
interface symbolicElement supports symbolic,  drawableElement,  etc.
 
    predicates
       run: () -> clause*
end interface symbolicElement 
 
class symbolicElement : symbolicElement
 
   constructors
 
      newModel: (string ModelName).
      new: (string ClassName).
      new: (string Name, symbolicElement ParentElement).
 
end class symbolicElement 
 
implement symbolicElement
      supports symbolic
      inherits drawableElement, etc.
 
end implement symbolicElement

The Symbolic Language

Clause is the base for the Symbolic Language.


clauses
interface symbolic
    open core
 
   domains
     program = clause*.
 
     clause =
       def(defClause); %1
       creator(createClause); %2
       ref(refClause); %3
       get(getClause); %4
       etc.
 
    domains
      symbolicType = ...
 
    domains 
      symbolicName = ...
 
end interface symbolic

The architecture

There is a PCMEF-implementation for the symbolic analysis architecture:

  1. F means Foundation: The clause defintion is the carrier for all information in symbolic analysis.
  2. E means Entity: SymbolicElement is the base class for all specific entities in the model.
  3. M means Mediator: The static part of SymbolicElement contains the transformations and handles for Mediator.
  4. C means Controller: Controller is a set of utilities to change status of the elements.
  5. P means Presentation: Presentation is a graph created from model elements.