Desc. : This file summarizes the changes of the BDDSearch 
        engine for research on BDD-based search in deterministic 
        and non-deterministic domains.	
Auth. : Rune M. Jensen
Date  : 04/06/02



VERSION 0.1 March 2002

  This is the basic version made by a combination
  of DETUMOP 0.3 and DOP 0.5.

  It accepts both NADL and PDDL problems but only for deterministic
  domains. Search is based in disjunctive partitions in the form
  of branching partitions.

  Search algorithms are: regular breadth-first BDD-based search:
    forward, backward and bidir , and SetA* and SetIDA*.

  BDDSearch is prepared for single-state versions of some of
  these algorithms as well.


VERSION 0.2 April 2002

  The BDD packages has been changed from BuDDy to CUDD.
  
VERSION 0.3 April, May 2002

  A comparison study show no particular advantage of using CUDD,
  so we continue with BuDDy. This version in addition includes:

  1) dynamic check of command parameters
  2) default check on each switch statement to avoid "hard to understand"
     incompletness bugs
  3) New algorithms
     a) A* single-state
     b) BDDA*
     c) pure-BDDA*   
     d) FminA*
     d) pureFminA*
     e) PubBDDA* 
     f) PubpureBDDA*
  4) introduced releveling of depths used by HSPr
  5) introduced weight x [0,1] for g and weight y [0,1] for h  

  OBS: This version was used for the AIJ experiments


VERSION 0.4 August 2002

  Integrating 2 non-deterministic search algorithms
     1) Strong universal planning
     2) Strong Heuristic planning

  Adding the statet-action pair printing class

VERSION 0.5 October 2002
   
  1) changing NADL frontend to extNADL
  2) cleaning code for nondeterministic search
  3) implementing Strong, StrongH, StrongCyclic,
     StrongCyclicH, Weak, WeakH
  

VERSION 0.6 November 2002
  
   1) implementing fault tolerant and optimal 
      fault tolerant planning
   2) changing StrongH to sound and complete versions  
   3) re-activated the dynamic variable reordering option
   4) implementing directed 1-fault tolerant planning
   5) changed difference between code and description in ICAPS-03
      from 1-faulttol : error states are not considered recovered if they
      only are covered by the 1-fault tolerant plan.
   6) Changing StrongCyclic and StrongCyclicH to the correct and complete
      version in "Strong cyclic planning revisited" Traverso, Vardi et. al 

VERSION 0.7 January 2002
  
   1) re-factoring code to accept environemnt actions.
      BDDS is restricted to a SINGLE system agent/process and 
      at most one environment agent/process. 

   2) non-deterministic algorithms accepts the new format
      But it is undefined what the fault-tolerant algorithms
      do given an environment 

   3) Changed the Strong, StrongCyclic, and Weak algorithms
      to work on sets of initial states

   4) removed buddy split supportsince this part of the BDD package 
      is notused in my current work