Limitations

If you find bugs, check this page, check The Ptolemy-Hackers Mailing List and then send email to the Ptolemy-Hackers mailing list or to ptolemy at eecs berkeley edu

In your email, please be sure to list

  • What operating system you are operating under (Windows XP SP1? Solaris 8?)
  • What version of Java you are running. (Run java -version, or start up HyVisual, view one of the demos and then select View -> JVM Properties and look for the value of the java.version property. Note that HyVisual 2.2-beta requires Java 1.4 or later.)
  • Whether the problem occurs in
  • The downloaded and installed version
  • The Web Start version
  • Release Limitations

    • Ptolemy II requires Java 1.4 or later because we use the java.net.URI class. If Ptolemy II fails to start and you see a message about java.net.URI or possibly ptolemy.vergil.VergilApplication, the the problem could be that you are running a version of Java that is older than Java 1.4
    • Unfortunately, there is a bug in Java 1.4 under Windows XP that may that causes XP to hang when exiting a Java application. For details, see http://developer.java.sun.com/developer/bugParade/bugs/4713003.html
      The workaround is to start the java interpreter with -Dsun.java2d.noddraw=true
      Apparently this is fixed in Java 1.4.1_02 and possibly in JRE 1.4.0_03
      The Java bug page says:
      Note: ifyou can't disable the use of ddraw by java prior to installing it, you can still disable the use of ddraw by the system, install java, set the -Dsun.java2d.d3d=false in the plugin control panel, and then enable ddraw in the system again.

      The ddraw can be disabled by either running "Program Files/DirectX/Setup/dxsetup" application, or in the Display Properties panel: click 'Advanced' button, then go to 'Troubleshoot' tab, and set the slider on the second mark from the left.

    • HyVisual requires Java 1.4, which under Mac OS X requires Mac OS X 10.2. However, because Java 1.4 is still under development und Mac OS X, there are many limitations under Mac OS X. See HyVisual Notes for Mac OS X for details.
    • If a URL ends with #in_browser, then Ptolemy II will invoke the User's web browser. Unfortunately, this does not always work, especially under Windows if Netscape is already running. The workaround is to exit Netscape and let Ptolemy II start up Netscape for you.
    • Web Start issues:
      • Viewing a pdf file may bring up a blank window along with the pdf file. Running the code generator may bring up a blank window while the java or javac processes are running. We've seen this problem under Windows 98. The workaround is to access the documentation via http://ptolemy.eecs.berkeley.edu/hyvisual/hyvisualdoc.htm
      • Web Start is limited to about 65Mb of memory
        If you try to run all the demos, then eventually you may see the following in the Web Start console
        761 ms. Memory: 65280K Free: 3614K (6%)
        7471 ms. Memory: 65280K Free: 931K (1%)
        Exception occurred during event dispatching:
        java.lang.OutOfMemoryError
        
        	<<no stack trace available>>
        
        One workaround is to request garbage collection by doing File -> View -> JVM Properties -> Request Garbage Collection

    Limitations in the Actor Libraries

    • The actor library is far from complete.
    • The Expression actor does not properly propagate type constraints in an expression-dependent fashion. It works correctly for double-valued expressions of double-valued inputs.
    • The Ptolemy parameter parser uses comma "," to separate elements in an array. This causes problems when Ptolemy is run on European machines that use a comma "1,0" instead of a period "1.1" in floating point numbers.
    • You can't use column matrices in FSM actions, because of the semicolon delimiter.

    Limitations in the User Interface

    Below are some of the limitations of Vergil, the Ptolemy II Graphical User Interface.
    • When setting the type of a port, we should provide a combo box that lists the common ports
    • When creating a Modal Model, use Control-Right-Button to drawn arcs between nodes. One potential workaround would be to have an information message in the status bar about this.
    • You should not change the names of built in ports - The port mechanism should disallow port name changes on ports that are named in Java. The UI could recognize this. The UI should not allow the user to remove built in Java defined ports.
    • It should be possible to reorder ports.
    • Manually setting of the types of actors like ArrayToSequence that have constraints on their element types can cause problems.
    • The Undo mechanism is under development. Not all actions undoable.
    • The documentation for the parameter utilitie is not included
    • The save in library and make hierarchy facilities are under development
    • Weak support for multiports in the graph editor.
    • It is difficult to control wire routing.
    • Cannot have more than one vertex in a connection.
    • No mechanism to set the width of a relation.
    • The integrated web browser is not a full-featured browser.
    • Icon editor not yet integrated.
    • Debugger not yet integrated.
    • It is difficult to add actors to the libraries.
    • No dynamic class reloading.

    Changes

    Changes between 2.2-beta-2 and 2.2-beta-3

  • If HyVisual is started up using Web Start or the ZeroG InstallAnywhere installer, then the notion of the current directory is changed to the user's home directory. Previously, the current directory would be something like c:/Program Files/Ptolemy/HyVisual 2.2-beta-2
  • Professor Lee tuned the configuration and removed actors that will not work in HyVisual
  • Professor Lee fixed the SquareWave demo so that the user is no longer prompted to save the model after running it.
  • If HyVisual gets an error while reading in the configuration, a dialog box pops up with the stack trace. Previously, if the user started HyVisual from a menu, then stderr and stdout would not be visible to the user and if there was an error, the user would not see any of the diagnostics.
  • The documentation for the ptolemy.actors.parameters package is included in the release so that the 'Get Documentation' right menu choice works for IntRangeParameter and portParameter, which are available under the Utilities tree branch. Note that 'Get Documentation' does not work for parameter
  • Changes between 2.2-beta and 2.2-beta-2

  • Professor Lee improved the annotations of many of the models
  • Minor spelling fixes