-r(see the section below, "Copying objects" on page 2-55). You can modify the copied version.
2.2.1 Starting Ptolemy
In any terminal window, change to the master demo directory:
vem console window at the upper left of your screen, a palette with icons of demonstrations below that, and a message window identifying the version of Ptolemy, as shown in figure
Once you get all three windows, you have started two processes: the graphical editor,
vem, and a process named
pigiRpc that contains the
pigi code and the Ptolemy kernel. The
vem window prints the textual commands corresponding to your selections with the mouse. Watching the
vem window is useful in diagnosing mistakes, such as drawing a box when you meant to draw a line. The
vem console window also displays debugging messages, as well as the error and warning messages that appear in popup windows.
vem console window will terminate the entire program.
The palette window contains icons. Five different types of icons are used in
pigi, as shown in figure
2.2.2 Exploring the menus
Place the mouse cursor on the icon labeled "SDF". Get the
pigi command menu by holding the shift key and clicking the middle mouse button. This style of menu is called a "walking menu." Make sure you hold the shift button. The resulting command menu is shown below:
The names displayed in the left main menu are only headers. To see the individual commands under each header, you must move the mouse to the arrows at the right of the menu. The sub-menu that appears on the right contains commands. Clicking any mouse button with a command highlighted as shown on the right will execute that command. To remove the menu without executing any command, simply click a mouse button anywhere outside the menu.
2.2.3 Traversing the hierarchy
Go to the "Window" sub-menu, and execute the look-inside command, as shown above on the right. A new palette will open, containing icons representing further palettes. Look inside the first of these, labeled "Basic". The icons inside contain application programs, called "universes" in Ptolemy. The two palettes you have just opened are shown in figure
Note in the Ptolemy menu that the look-inside directive has an "i" next to it. This is a "single key accelerator." Without using the walking menu, you can look inside any icon by simply placing the mouse cursor and hitting the "i" key on the keyboard. The single-key accelerators are extremely useful. In time, you will find that you use the menu only for commands that have no accelerator, or for which you cannot remember the accelerator. The Ptolemy commands obtained through the above menu are summarized in table 2-2.
Look inside the first demo on the third row, labeled "
sinMod". You will see the schematic shown in figure
PT_DISPLAY(see "Environment variables" on page 2-61).
2.2.4 Running a Ptolemy application
To run the
sinMod system using the walking menu, place the mouse cursor anywhere in the window containing the
sinMod schematic, i.e., your cursor should be in the window that contains the following schematic:
Again holding the shift key, click the middle mouse button. Go to the "Exec" sub-menu, and select "run" by clicking any button. Notice that typing an "R" would have had the same effect. The following control panel pops up:
pxgraphwindow by drawing boxes; to draw a box, just drag any mouse button. This causes a new window to open with a display of only the area that your box enclosed. Although the new window covers the old, if you move it out of the way, you can see both at once. Any of the now numerous open windows can be closed with a control-d.
2.2.5 Examining schematics more closely
Place the mouse cursor in any schematic or palette window, and click the middle mouse button without holding the shift key. The
vem command menu, which is different from the
pigi command menu, appears. This menu is the same style of "walking menu" as the
pigi menu, and is shown below:
vem menu is used for manipulating the graphical description of an application. The commands obtained through this menu are summarized in table
2-3, and explained in full detail in The Almagest.
A few additional window manipulations will prove useful almost immediately. In any of the
vem windows, you can closely examine any part of the window by drawing a box enclosing the area of interest and typing an "o". Like in a
pxgraph window, this causes a newwindow to open, showing only the enclosed area. Unlike
pxgraph windows, typing the "o" is necessary. In addition, you can enlarge a window using your window manager manipulation, and type an "f" to fill the window with the schematic. You can also zoom-in (or magnify) by typing a "z", and zoom-out by typing a "Z" (see table
2-3 on page 2-22). These and other
vem commands are referenced again later.
2.2.6 Invoking on-line documentation for stars
You may wish to understand exactly how this
sinMod example works. There are several clues to the functionality of the stars. After a while, the icons themselves will be all you will need. At this point, you can get several levels of detail about them. First, you will want to know the name of each star. If you have closed the
sinMod window, open it again. Notice the names that appear on each of the icons. In more complicated schematics, when the icons are much smaller, the names will not show. You can zoom-in on a region of the window to see the names. Alternatively, you can place the mouse on any icon and issue the "show-name" command (in the "Other" menu), or type "n".
singen block at the left of the
sinMod schematic. To understand its function, place the mouse cursor on it, and execute the Other:profile command. Here "Other" refers to the command category and "profile" to the command in the submenu (you may also type ","). This command invokes a window that summarizes the behavior of the block, as shown below:
XMgraph block at the right of the schematic. The man command requires that the program
xditview be installed and in your path. It also requires a program
ditroff. If it fails to find these programs, the manual page will be formatted with nroff and displayed on the standard output, which is considerably less useful. In the next version of Ptolemy, the documentation will be formatted using HTML and displayed on-line. The ultimate documentation for any block is, of course, its source code. For the
singen block, the source is another schematic. Use the "look-inside" command (using the accelerator key "i") to see it. Recall that you can also look at the source code of the lowest level blocks (called stars) by looking inside them.
2.2.7 More extensive exploration of the demos
You can safely explore other demos in the palette by the same mechanism. The
butterfly demo at the upper left of the "basic" palette in figure
2-3 is particularly worthwhile. The demos in this and other palettes are briefly summarized in
"An overview of SDF demonstrations" on page 3-111.
init.pal palette in figure
2-1 contains icons leading to a top-level demo directory for each domain distributed with Ptolemy. Some of these are labeled "experimental". These domains largely reflect research in progress and should be viewed as concept demonstrations only. Most will not run under
ptiny. The mature domains have no such label, although even these domains contain some experimental work. A quick tour of the basic capabilities can be had by looking inside the icon labeled "quick tour" in the start-up palette shown in figure
2-1. Each time you encounter a universe, run it.
2.2.8 What's new
For readers familiar with previous versions of Ptolemy, you may wish to take a tour of the new features only. The "What's New" icon in the
init.pal palette in figure
2-1 leads to such a tour. Look inside it and you will see an icon for each of the last several releases. Open any one and explore the icons therein. Each time you encounter a universe, feel free to run it.