PTOLEMY II - CiteSeerX

Authors: Edward A. Lee
Steve Neuendorffer
Contributor: Christopher Hylands
7.1 Introduction
7
MoML
Ptolemy II models might be simulations (executable models of some other system) or implementations
(the system itself). They might be classical computer programs (applications), or any of a number
of network-integrated programs (applets, servlets, or CORBA services, for example).
Models can be specified in a number of ways. You can write Java code that instantiates components,
parameterizes them, and interconnects them. Or you can use Vergil (see the Vergil chapter
above) to graphically construct models. Vergil stores models in ASCII files using an XML schema
called MoML. MoML (which stands for Modeling Markup Language) is the primary persistent file
format for Ptolemy II models. It is also the primary mechanism for constructing models whose definition
and execution is distributed over the network.
This chapter explains MoML. Most users will not need to edit MoML files directly. Use Vergil
instead. Occasionally, however, it is useful to examine and/or edit MoML files directly.
MoML is a modeling markup schema in the Extensible Markup Language (XML). It is intended
for specifying interconnections of parameterized components. A MoML file can be executed as an
application using any of the following commands,
ptolemy filename.xml
ptexecute filename.xml
vergil filename.xml
moml configuration.xml filename.xml
These commands are defined in the directory $PTII/bin, which must be in your path 1 , where $PTII
is the location of the Ptolemy II installation. In all cases, the filename can be replaced by a URL. The
Heterogeneous Concurrent Modeling and Design 191