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A.12.  )help
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User Level Required:  interpreter
 
Command Syntax: 
 
  - )help
  - )help commandName
  - )help syntax
 
Command Description: 
 
This command displays help information about system commands. If you issue
 
)help
 
then this very text will be shown. You can also give the name or abbreviation
of a system command to display information about it. For example,
 
)help clear
 
will display the description of the )clear system command.

The command 

)help syntax

will give further information about the FriCAS language syntax.
 
All this material is available in the FriCAS User Guide and in HyperDoc. In
HyperDoc, choose the Commands item from the Reference menu.
 
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A.1.  Introduction
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System commands are used to perform FriCAS environment management. Among the
commands are those that display what has been defined or computed, set up
multiple logical FriCAS environments (frames), clear definitions, read files
of expressions and commands, show what functions are available, and terminate
FriCAS.
 
Some commands are restricted: the commands
 
)set userlevel interpreter
)set userlevel compiler
)set userlevel development
 
set the user-access level to the three possible choices. All commands are
available at development level and the fewest are available at interpreter
level. The default user-level is interpreter. In addition to the )set command
(discussed in description of command )set ) you can use the HyperDoc settings
facility to change the user-level. Click on [Settings] here to immediately go
to the settings facility. 
 
Each command listing begins with one or more syntax pattern descriptions plus
examples of related commands. The syntax descriptions are intended to be easy
to read and do not necessarily represent the most compact way of specifying
all possible arguments and options; the descriptions may occasionally be
redundant.
 
All system commands begin with a right parenthesis which should be in the
first available column of the input line (that is, immediately after the
input prompt, if any). System commands may be issued directly to FriCAS or be
included in .input files.
 
A system command argument is a word that directly follows the command name
and is not followed or preceded by a right parenthesis. A system command
option follows the system command and is directly preceded by a right
parenthesis. Options may have arguments: they directly follow the option.
This example may make it easier to remember what is an option and what is an
argument:
 
         )syscmd arg1 arg2 )opt1 opt1arg1 opt1arg2 )opt2 opt2arg1 ...
 
In the system command descriptions, optional arguments and options are
enclosed in brackets (``['' and ``]''). If an argument or option name is in
italics, it is meant to be a variable and must have some actual value
substituted for it when the system command call is made. For example, the
syntax pattern description
 
)read fileName [)quietly]
 
would imply that you must provide an actual file name for fileName but need
not use the )quietly option. Thus
 
)read matrix.input
 
is a valid instance of the above pattern.
 
System command names and options may be abbreviated and may be in upper or
lower case. The case of actual arguments may be significant, depending on the
particular situation (such as in file names). System command names and
options may be abbreviated to the minimum number of starting letters so that
the name or option is unique. Thus
 
)s Integer
 
is not a valid abbreviation for the )set command, because both )set and )show
begin with the letter ``s''. Typically, two or three letters are sufficient
for disambiguating names. In our descriptions of the commands, we have used
no abbreviations for either command names or options.
 
In some syntax descriptions we use a vertical line ``|'' to indicate that you
must specify one of the listed choices. For example, in
 
)set output fortran on | off
 
only on and off are acceptable words for following boot. We also sometimes
use ``...'' to indicate that additional arguments or options of the listed
form are allowed. Finally, in the syntax descriptions we may also list the
syntax of related commands.

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Other help topics
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Available help topics are: 

abbreviations assignment blocks     browse     boot       cd
clear         clef       close      collection compile    display
edit          fin        for        frame      help       history
if            iterate    leave      library    lisp       load
ltrace        parallel   pquit      quit       read       repeat
savesystem    set        show       spool      suchthat   synonym
system        syntax     trace      undo       what       while

Available algebra help topics are:

