NAME

       yorick - interpreted language for numerical analysis and postprocessing

SYNOPSIS

       yorick [ -i file1.i [ -i file2.i [ ... ]]]
       yorick -batch file.i

DESCRIPTION

       Yorick is an interpreted language like Basic or Lisp, but far faster.  It features:

       *  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:
        help
       This will tell you the name of the Yorick 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 i/ 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:
        #include "demo1.i"
        demo1
       After the little movie runs on your X window system display, try:
        help, demo1
       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:
        #include "testg.i"
        grtest
       You  can get a description of the various files in the interpreted library by typing (as a
       command to Yorick):
        library

   Options
       -i file.i           includes the Yorick source file file.i  as  Yorick  starts.   This  is
                           equivalent to the #include directive after Yorick has started.

       -batch file.i       includes  the  Yorick  source  file  file.i  as  Yorick  starts.  Your
                           customization file custom.i, if any, is not read, 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.

AUTHOR

       David H. Munro, Lawrence Livermore National Laboratory

FILES

       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):

       Y_SITE/doc/*             documentation, including the quick reference sheets, user manual,
                                and alphabetized collections of all the online help messages.

       Y_SITE/i/*.i             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.

       Y_SITE/g/*               graphics style sheets, palettes, and PostScript template

       Y_SITE/i0/*.i            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.

BUGS

       If x is a scalar int, long, or double,
        x(1)= scalar-expression
       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/i/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 not easy.

       The nice= and restrict= keywords to the limits function don't seem to work properly.

       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 people.

       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.

SEE ALSO

       gist(1)