.TH YORICK 1 "1994 August 30"
[ ... ]]]
is an interpreted language like Basic or Lisp, but far faster. It
A C-like language, but without declarative statements. Operations
between arrays produce array results, which is one reason for
Yorick's high speed.
An X window system interactive graphics package. Concentrates on
x-y plots and filling and contouring quadrilateral meshes. Also
handles cell arrays. Graphics can be output to binary CGM or
PostScript files as well. A separate CGM browser, gist(1), is included.
A binary file package which can read or write floating point formats
which are foreign to the machine where Yorick is running. Thus, you
can share binary files freely on a heterogeneous network.
A library of functions written in the Yorick language. These
include Bessel, gamma, and related functions, multiple key sorting,
spline, rational function, and least squares fitting, and routines
to read and write netCDF files.
Provisions for embedding compiled subroutines and functions within
a Yorick interpreter. A compiled package which solves matrices and
performs FFTs is supplied.
You cannot learn to program in Yorick by reading this man page. Instead,
start Yorick (with no arguments) and type:
This will tell you the name of the Yorick
.I site directory
at your site. The site directory contains a doc/ subdirectory; read
the README file there to find out about more documentation. The
Yorick user manual is in project GNU's TeXinfo format, which can be
either printed or read online as hypertext using the info command in
GNU Emacs. Also available are a set of six quick reference sheets (as
PostScript), and alphabetized collections of all of Yorick's online
help comments (accessible via the help command). Finally, the
include/ subdirectory of the Yorick site directory is a library of
functions which are written in the Yorick language, which are also
helpful as examples of how to write Yorick programs.
To demonstrate Yorick, start Yorick and type the following two lines:
After the little movie runs on your X window system display, try:
Follow the SEE ALSO references in this help message by issuing additional
help commands. Also, the help command will print the full pathname of the
demo1.i file. Read this file to see how the demo1 function works.
You can repeat this procedure with demo2.i, demo3.i, and demo4.i:
demo1 - movies of sound and shock waves
demo2 - movies of a drumhead oscillating
demo3 - movie of a chaotic pendulum
demo4 - visualization of the flow field around an airfoil
You can run a crude tutorial introducing all of the Yorick graphics
commands by starting Yorick and typing:
You can get a description of the various files in the interpreted
library by typing (as a command to Yorick):
.RI -i \0file.i
includes the Yorick source file
as Yorick starts. This is equivalent to the #include directive after
Yorick has started.
.RI -batch \0file.i
includes the Yorick source file
as Yorick starts. Your customization file custom.i, if any, is
and Yorick is placed in batch mode. Use the help command on the batch
function (help, batch) to find out more about batch mode. In batch
mode, all errors are fatal; normally, Yorick will halt execution and
wait for more input after an error.
David H. Munro, Lawrence Livermore National Laboratory
Y_SITE refers to the Yorick site directory; use the help command
to find its name at your site (the variable Y_SITE also contains the
name of the site directory):
documentation, including the quick reference sheets, user manual, and
alphabetized collections of all the online help messages.
a library of interpreted Yorick functions. Here are Bessel, gamma, and
beta functions, multiple key sorting, curve fitting functions, and more.
The file readme.i has a more complete description.
graphics style sheets, palettes, and PostScript template
include files Yorick needs to read whenever it starts. Several of these
contain the definitions of functions which you may need to read in order
to fully understand their operation, or as examples of Yorick programs.
If x is a scalar int, long, or double,
will fail. You normally wouldn't do the assignment like this (you
would just redefine x). Usually, you can work around this bug using
the merge function; do "help, merge" and read Y_SITE/include/bessel.i for
examples of the merge function.
Expressions like openb("file_containing_x").x do not work, even though
they are syntactically and logically correct. It turns out the file
closes before the data can be read. This one may be fixable, but it's
The nice= and restrict= keywords to the limits function don't seem to
Clipping of filled mesh plots (the plf command) is not always correct.
Text -- particularly curve markers -- is clipped by not drawing it;
the absence of partial characters at the edge of a plot puzzles most
Recursive debug mode (debugging an error which occurred while you were
debugging) doesn't work. Also, Yorick can't always get into and out
of its debug mode properly. Occasionally, it will get the line number
where an error occurred wrong, especially if the error was in the
condition or increment clause of a for loop.
On pseudocolor displays, a color image may require you to move the
mouse into yorick's X window to display properly, if you use the
private=1 option of the window command. Unless your window manager
allows you to set colormap focus independently of keyboard focus, this
can be annoying.
Unless you use the dump=1 keyword with the hcp_file command, PostScript
and CGM graphics output files will contain gray scale equivalents of the
color images you see on your screen. If you use a color printer, this
can be confusing.
.SH SEE ALSO