Petriscript

Petriscript

PetriScript is a modelling language for Petri Nets, designed by [http://lip6.fr/Alexandre.Hamez Alexandre Hamez] and [http://www-src.lip6.fr/~Xavier.Renault Xavier Renault] .

The CPN-AMI platform provides many tools to work on Petri net such as verifying or model-checking tools. It was easily possible to graphically design simple Petri nets with [http://www-src.lip6.fr/logiciels/mars/MACAO Macao] , but various works made internally at [http://www.lip6.fr LIP6] reveal that it was needed to automate such task.

Therefore PetriScript has been designed to provide some facilities in modelling places-transition and coloured Petri nets within the CPN-AMI platform.

Its main purpose is to automate modelling operations on Petri nets such as merging, creating, and connecting nodes. Thus, it supports almost everything needed like macros, loops control, lists, string and arithmetic expressions,..., and avoids to the maximum the intervention of the user. Its syntax is more or less Ada-like.

For example, the following script produces a FIFO with 3 sections:

define(FIFO_SIZE,3) define(FIFO_BASE_X,100) define(FIFO_BASE_Y,100) define(FIFO_STEP,120) int $wave := 0; for $wave in 1..FIFO_SIZE loop create place "Slot_" & '$wave' (x FIFO_BASE_X + FIFO_STEP * $wave, y FIFO_BASE_Y); create place "Empty_" & '$wave' (x FIFO_BASE_X + FIFO_STEP * $wave, y FIFO_BASE_Y + 100, marking "1"); end loop; for $wave in 1..FIFO_SIZE+1 loop create transition "t" & '$wave -1' & "_to_" & '$wave' (x FIFO_BASE_X + FIFO_STEP * $wave - FIFO_STEP / 2, y FIFO_BASE_Y + 50); if $wave < FIFO_SIZE+1 then connect "1" transition "t" &'$wave -1' & "_to_" & '$wave' to place "Slot_" & '$wave'; connect "1" place "Empty_" & '$wave' to transition "t" &'$wave -1' & "_to_" & '$wave'; end if; if $wave > 1 then connect "1" transition "t" &'$wave -1' & "_to_" & '$wave' to place "Empty_" & '$wave - 1'; connect "1" place "Slot_" & '$wave - 1' to transition "t" &'$wave -1' & "_to_" & '$wave'; end if; end loop; set transition "t0_to_1" to (name "FIFO_Start"); set transition "t" & 'FIFO_SIZE' & "_to_" & 'FIFO_SIZE + 1' to (name "FIFO_End");

Which produces the following graph:

Here is another example that shows the power of PetriScript:

define(X,250) define(Y,350) define(radius,50) define(R,150) define(SECTIONS,15) define(INNER_ANGLE,360/SECTIONS) define(OUTTER_ANGLE,360/(2*SECTIONS)) int $i := 0; int $j := 0; for $i in 1.. SECTIONS loop create place "F" & '$i' ( x X, y Y, r radius, t $i * INNER_ANGLE); create place "Section_" & '$i' ( x X, y Y, r R, t $i * INNER_ANGLE); create transition "t" & '$i' & "_to_" & '$i mod SECTIONS + 1' ( x X, y Y, r R, t $i * INNER_ANGLE + OUTTER_ANGLE); end loop; for $i in 1.. SECTIONS loop connect place "Section_" & '$i' to transition "t"&'$i' & "_to_" & '$i mod SECTIONS + 1'; connect transition "t" & '$i' & "_to_" & '$i mod SECTIONS + 1' to place "Section_" & '$i mod SECTIONS + 1'; if $i /= 1 then connect place "F" & '$i' to transition "t" & '$i-1' & "_to_" & '$i'; else connect place "F1" to transition "t" & 'SECTIONS' & "_to_" & '1'; end if; connect transition "t" &'$i mod SECTIONS + 1' & "_to_" & '($i+1) mod SECTIONS + 1' to place "F" & '$i'; end loop; for $i in 1.. SECTIONS loop if $i mod 3 = 0 then set place "Section_" & '$i' to marking "1"; else set place "F" & '$i' to marking "1"; end if; end loop;

Which produces the following graph:

A full documentation is available [http://www-src.lip6.fr/logiciels/mars/CPNAMI/MANUAL_SERV/PetriScript_Reference_Manual.pdf here]


Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать курсовую

Look at other dictionaries:

  • Petri net — A Petri net (also known as a place/transition net or P/T net) is one of several mathematical modeling languages for the description of distributed systems. A Petri net is a directed bipartite graph, in which the nodes represent transitions (i.e.… …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”