Difference between pages "Event-B Qualitative Probability User Guide" and "Rodin Platform 2.1.1 Release Notes"

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[[User:Son]] is in charge of the plug-in.
 
 
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== Introduction ==
+
Rodin 2.1.1 is a maintenance release: as such, it contains only bug fixes. For more information, see [[Rodin_Platform_2.1_Release_Notes]].
Event-B Qualitative Probability plug-in provides supports for reasoning about termination with probability 1 (almost-certain termination).
 
For more details about the principles on XEvent-B, see the [[Qualitative Probability | Qualitative Probability page]].
 
  
== Installing and Updating ==
+
== What's New in Rodin 2.1.1 ? ==
The plug-in is available through the main Rodin Update Site under '''Modelling Extension''' category.
 
  
== News ==
+
* Fixed bugs:
* 23.11.2011: Version 0.2.1 released for Rodin 2.3.*
+
** ArrayIndexOutOfBoundsException during a build
* 10.04.2012: Version 0.2.1 is compatible with Rodin 2.4.*
+
** IndexOutOfBoundsException when building a theory (with [[Theory_Plug-in|Theory Plug-in]] installed)
* 14.05.2012: Version 0.2.1 is compatible with Rodin 2.5.*
+
** Auto-tactic profile preference bugs
* 09.03.2015: Version 0.2.2 is released with Rodin 3.x.x
+
** Various UI bugs (prover interface, rule details, tactic profiles)
* 09.10.2015: Version 0.2.3 is released
 
* 23.07.2017: Version 0.2.4 is released
 
  
== Technical References ==
+
* Changes for plugin-developers
* Thai Son Hoang. '''Reasoning about almost-certain convergence properties using Event-B'''. Science of Computer Programming, 81:108–121, February 2014 © Elsevier. [https://doi.org/10.1016/j.scico.2013.08.006 SCP website] (''Please use this article as the reference for the plug-in).
+
:None
** Extended version of the EASST paper (below).
 
** Probablistic convergence event with refinement
 
** Constraints on how (not-) to refine probabilistic events.
 
** Example: Duelling cowboys
 
** Example: Rabin's choice coordination.
 
** Example: Herman's probabilistic self-stabilization.
 
* E. Yilmaz, T.S. Hoang. '''Development of Rabin’s Choice Coordination Algorithm in Event-B'''.  In ''Automated Verification of Critical Systems 2010'', volume 35 of ''Electronic Communications of the EASST'' © EASST. [http://journal.ub.tu-berlin.de/eceasst/article/view/548 EASST website]
 
** Probablistic convergence event with refinement
 
** Constraints on how (not-) to refine probabilistic events.
 
** Example: Rabin's Choice Coordination.
 
* S. Hallerstede, T.S. Hoang. '''Qualitative Probabilistic Modelling in Event-B'''. In ''IFM 2007: Integrated Formal Methods, 6th International Conference Proceedings'', Oxford, UK, July 2-5, 2007, volume 4591 of LNCS © Springer-Verlag. [http://dx.doi.org/10.1007/978-3-540-73210-5_16 Springer website]
 
** Initial idea about probabilistic convergence event.
 
** New modelling elements: Variant bound
 
** New proof obligations: '''PRV''', '''BND''', '''FINACT'''.
 
** Example: Resolve contention in IEEE 1395 (Firewire protocol).
 
  
== Usage ==
+
== Installing ==
We illustrate the usage of the plug-in using the example of contention resolving (part of IEEE 1394 Firewire protocol). The description of the problem is as follows.
 
  
Two processes in contention use a probabilistic protocol to resolve the problem. In each step, each process probabilisitcally choose to communicate in either short or long delay.  The contention is resolved when the processes choose different delays.
+
=== Upgrading from Rodin 2.1 ===
  
We start with a non-deterministic model of the system
+
* download archive [http://sourceforge.net/projects/rodin-b-sharp/files/Core_%20Rodin%20Platform/2.1.1/rodin-2.1.1-repo.zip/download rodin-2.1.1-repo.zip]
* Boolean variables <math>x</math> and <math>y</math> represent the choice for each process: <math>TRUE</math> for short delay <math>FALSE</math> for long delay.
+
* launch Rodin 2.1
 +
* Help > Install New Software... > Add... > enter a name (for instance "Rodin 2.1.1") then
 +
: Archive... > select the rodin-2.1.1-repo.zip archive
 +
* set options in the bottom of the page:
 +
:* check
 +
:** "Show only the latest versions of available software"
 +
:** "Hide items that are already installed"
 +
:* uncheck
 +
:** "Group items by category"
 +
:** "Contact all update sites..."
 +
: the central area should now list 5 entries
 +
* select "Rodin Platform", click "Next"
 +
: a message informs "Your original request has been modified.  See the details."
 +
: "Rodin Platform" is already installed, so an update will be performed instead.
 +
* click Next, accept license, finish and restart
  
* Resolving contention is model as an event of the model with guard <math>x = y</math> (i.e. keep trying when the choices are identical).
+
=== Downloading ===
[[Image:contention-nondet.jpg|480px|alt=Alt|Nondeterminsitc modelling of Contention problem]]
 
  
 +
[http://sourceforge.net/projects/rodin-b-sharp/files/Core_%20Rodin%20Platform/2.1.1/ http://sourceforge.net/projects/rodin-b-sharp/files/Core_%20Rodin%20Platform/2.1.1/]
  
=== Probabilistic Modelling ===
+
== Disclaimer ==
* Set event '''resolve''' to be probabilistic convergence by setting its convergence attribute to be ''convergent'' and the probabilistic attribute of '''resolve''' from ''standard'' to ''probabilistic''.
+
Since Rodin is continuously maintained, several unsoundness bugs which have been encountered were investigated and fixed. However, despite the total commitment of our teams to insure the soundness of the platform, some unexpected and unknown soundness issues could remain. We would be grateful if you would report these issues to the [mailto:rodin-b-sharp-devel@lists.sourceforge.net development mailing list].
[[Image:contention-prob.jpg|400px|alt=Alt|Probabilistic modelling of contention]]
 
  
* Set <math>\Bool \setminus \{x, y\}</math> as the variant of the model
+
== About ==
[[Image:contention-variant.jpg|150px|alt=Alt|Variant for the probabilistic convergent event]]
+
Rodin Platform from release branch: branches/RodinCore/2.1.1 r10985
  
* Create a new bound element (right-click on the machine name and choose ''Add Child''/Event-B Bound Element).
+
Made of Rodin 2.1 plus following trunk revisions (change log available in SourceForge downloads):
[[Image:contention-bound-create.jpg|500px|alt=Alt|Create the bound element]]
+
10768; 10800; 10801; 10806; 10807; 10860; 10861; 10863; 10870; 10872; 10876; 10877; 10880; 10879; 10915; 10916; 10940
  
* Set <math>\Bool</math> as the bound of the model
 
[[Image:contention-bound.jpg|100px|alt=Alt|Bound for the probabilistic convergent event]]
 
  
* Save the model
+
Developer Release date : 11/03/2011.
 +
User Release date : 15/03/2011.
  
=== Proof Obligations ===
+
[[Category:Rodin Platform Release Notes]]
* The model should have 3 proof obligations including '''resolve/PRV'''.
 
[[Image:contention-po.jpg]]
 
 
 
* The goal of proof obligation '''resolve/PRV''' is <math>\exists x^\prime, y^\prime \qdot \Bool \setminus \{x^\prime, y^\prime\} \subset \Bool \setminus \{x, y\}</math>.  With hypothesis <math>x = y</math> (from the guard of the event), the proof obligation can be discharged by instantiating different values for <math>x^\prime</math> and <math>y^\prime</math> (e.g. <math>\True</math> for <math>x^\prime</math> and <math>\False</math> for <math>y^\prime</math>). Alternatively, the obligation can be interactively discharge using '''p1''' (AterlierB Predicate Prover on lasso'd hypotheses) directly as shown below
 
[[Image:resolve-prv.jpg]]
 
 
 
== Explanations for some warning and error messages ==
 
 
 
* '''Missing variant''' warning
 
** Problem: [[Image:contention-novariant.jpg|500px|alt=Alt|Missing variant]]
 
** Explanation: User needs to provide a variant for probabilistic convergence events.
 
** Solution: Add a variant to the model
 
 
 
 
 
* '''Missing bound''' error
 
** Problem: [[Image:contention-nobound.jpg|400px|alt=Alt|Missing bound]]
 
** Explanation: The variant for probabilistic events need to be bounded above.
 
** Solution: Add a bound to the model (using Edit page of the standard Rodin editor).
 
 
 
== Additional features to be investigated/implemented ==
 
* ''Proof hints'': Select event guards when creating proof obligations, such as PRV and BND
 
 
 
* ''Finer-grain for probabilisitc attribute''. The probabilistic attribute might/should be attached to individual assignment and/or parameter of the event.
 

Revision as of 17:36, 11 March 2011

Rodin 2.1.1 is a maintenance release: as such, it contains only bug fixes. For more information, see Rodin_Platform_2.1_Release_Notes.

What's New in Rodin 2.1.1 ?

  • Fixed bugs:
    • ArrayIndexOutOfBoundsException during a build
    • IndexOutOfBoundsException when building a theory (with Theory Plug-in installed)
    • Auto-tactic profile preference bugs
    • Various UI bugs (prover interface, rule details, tactic profiles)
  • Changes for plugin-developers
None

Installing

Upgrading from Rodin 2.1

  • download archive rodin-2.1.1-repo.zip
  • launch Rodin 2.1
  • Help > Install New Software... > Add... > enter a name (for instance "Rodin 2.1.1") then
Archive... > select the rodin-2.1.1-repo.zip archive
  • set options in the bottom of the page:
  • check
    • "Show only the latest versions of available software"
    • "Hide items that are already installed"
  • uncheck
    • "Group items by category"
    • "Contact all update sites..."
the central area should now list 5 entries
  • select "Rodin Platform", click "Next"
a message informs "Your original request has been modified. See the details."
"Rodin Platform" is already installed, so an update will be performed instead.
  • click Next, accept license, finish and restart

Downloading

http://sourceforge.net/projects/rodin-b-sharp/files/Core_%20Rodin%20Platform/2.1.1/

Disclaimer

Since Rodin is continuously maintained, several unsoundness bugs which have been encountered were investigated and fixed. However, despite the total commitment of our teams to insure the soundness of the platform, some unexpected and unknown soundness issues could remain. We would be grateful if you would report these issues to the development mailing list.

About

Rodin Platform from release branch: branches/RodinCore/2.1.1 r10985

Made of Rodin 2.1 plus following trunk revisions (change log available in SourceForge downloads):

10768; 10800; 10801; 10806; 10807; 10860; 10861; 10863; 10870; 10872; 10876; 10877; 10880; 10879; 10915; 10916; 10940


Developer Release date : 11/03/2011. User Release date : 15/03/2011.