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GNU Info File
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1996-09-28
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35KB
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640 lines
This is Info file octave.info, produced by Makeinfo-1.55 from the input
file octave.texi.
Copyright (C) 1993, 1994, 1995 John W. Eaton.
Permission is granted to make and distribute verbatim copies of this
manual provided the copyright notice and this permission notice are
preserved on all copies.
Permission is granted to copy and distribute modified versions of
this manual under the conditions for verbatim copying, provided that
the entire resulting derived work is distributed under the terms of a
permission notice identical to this one.
Permission is granted to copy and distribute translations of this
manual into another language, under the above conditions for modified
versions.
File: octave.info, Node: The Mode Line, Next: Basic Windows, Prev: Window Commands, Up: Window Commands
The Mode Line
-------------
A "mode line" is a line of inverse video which appears at the bottom
of an info window. It describes the contents of the window just above
it; this information includes the name of the file and node appearing in
that window, the number of screen lines it takes to display the node,
and the percentage of text that is above the top of the window. It can
also tell you if the indirect tags table for this info file needs to be
updated, and whether or not the info file was compressed when stored on
disk.
Here is a sample mode line for a window containing an uncompressed
file named `dir', showing the node `Top'.
-----Info: (dir)Top, 40 lines --Top---------------------------------------
^^ ^ ^^^ ^^
(file)Node #lines where
When a node comes from a file which is compressed on disk, this is
indicated in the mode line with two small `z''s. In addition, if the
info file containing the node has been split into subfiles, the name of
the subfile containing the node appears in the modeline as well:
--zz-Info: (emacs)Top, 291 lines --Top-- Subfile: emacs-1.Z---------------
When Info makes a node internally, such that there is no
corresponding info file on disk, the name of the node is surrounded by
asterisks (`*'). The name itself tells you what the contents of the
window are; the sample mode line below shows an internally constructed
node showing possible completions:
-----Info: *Completions*, 7 lines --All-----------------------------------
File: octave.info, Node: Basic Windows, Next: The Echo Area, Prev: The Mode Line, Up: Window Commands
Window Commands
---------------
It can be convenient to view more than one node at a time. To allow
this, Info can display more than one "window". Each window has its own
mode line (*note The Mode Line::.) and history of nodes viewed in that
window (*note `history-node': Node Commands.).
`C-x o' (`next-window')
Selects the next window on the screen. Note that the echo area
can only be selected if it is already in use, and you have left it
temporarily. Normally, `C-x o' simply moves the cursor into the
next window on the screen, or if you are already within the last
window, into the first window on the screen. Given a numeric
argument, `C-x o' moves over that many windows. A negative
argument causes `C-x o' to select the previous window on the
screen.
`M-x prev-window'
Selects the previous window on the screen. This is identical to
`C-x o' with a negative argument.
`C-x 2' (`split-window')
Splits the current window into two windows, both showing the same
node. Each window is one half the size of the original window,
and the cursor remains in the original window. The variable
`automatic-tiling' can cause all of the windows on the screen to
be resized for you automatically, please *note automatic-tiling:
Info Variables. for more information.
`C-x 0' (`delete-window')
Deletes the current window from the screen. If you have made too
many windows and your screen appears cluttered, this is the way to
get rid of some of them.
`C-x 1' (`keep-one-window')
Deletes all of the windows excepting the current one.
`ESC C-v' (`scroll-other-window')
Scrolls the other window, in the same fashion that `C-v' might
scroll the current window. Given a negative argument, the "other"
window is scrolled backward.
`C-x ^' (`grow-window')
Grows (or shrinks) the current window. Given a numeric argument,
grows the current window that many lines; with a negative numeric
argument, the window is shrunk instead.
`C-x t' (`tile-windows')
Divides the available screen space among all of the visible
windows. Each window is given an equal portion of the screen in
which to display its contents. The variable `automatic-tiling'
can cause `tile-windows' to be called when a window is created or
deleted. *Note `automatic-tiling': Info Variables.
File: octave.info, Node: The Echo Area, Prev: Basic Windows, Up: Window Commands
The Echo Area
-------------
The "echo area" is a one line window which appears at the bottom of
the screen. It is used to display informative or error messages, and to
read lines of input from you when that is necessary. Almost all of the
commands available in the echo area are identical to their Emacs
counterparts, so please refer to that documentation for greater depth of
discussion on the concepts of editing a line of text. The following
table briefly lists the commands that are available while input is being
read in the echo area:
`C-f' (`echo-area-forward')
Moves forward a character.
`C-b' (`echo-area-backward')
Moves backward a character.
`C-a' (`echo-area-beg-of-line')
Moves to the start of the input line.
`C-e' (`echo-area-end-of-line')
Moves to the end of the input line.
`M-f' (`echo-area-forward-word')
Moves forward a word.
`M-b' (`echo-area-backward-word')
Moves backward a word.
`C-d' (`echo-area-delete')
Deletes the character under the cursor.
`DEL' (`echo-area-rubout')
Deletes the character behind the cursor.
`C-g' (`echo-area-abort')
Cancels or quits the current operation. If completion is being
read, `C-g' discards the text of the input line which does not
match any completion. If the input line is empty, `C-g' aborts
the calling function.
`RET' (`echo-area-newline')
Accepts (or forces completion of) the current input line.
`C-q' (`echo-area-quoted-insert')
Inserts the next character verbatim. This is how you can insert
control characters into a search string, for example.
PRINTING CHARACTER (`echo-area-insert')
Inserts the character.
`M-TAB' (`echo-area-tab-insert')
Inserts a TAB character.
`C-t' (`echo-area-transpose-chars')
Transposes the characters at the cursor.
The next group of commands deal with "killing", and "yanking" text.
For an in depth discussion of killing and yanking, *note Killing and
Deleting: (emacs)Killing.
`M-d' (`echo-area-kill-word')
Kills the word following the cursor.
`M-DEL' (`echo-area-backward-kill-word')
Kills the word preceding the cursor.
`C-k' (`echo-area-kill-line')
Kills the text from the cursor to the end of the line.
`C-x DEL' (`echo-area-backward-kill-line')
Kills the text from the cursor to the beginning of the line.
`C-y' (`echo-area-yank')
Yanks back the contents of the last kill.
`M-y' (`echo-area-yank-pop')
Yanks back a previous kill, removing the last yanked text first.
Sometimes when reading input in the echo area, the command that
needed input will only accept one of a list of several choices. The
choices represent the "possible completions", and you must respond with
one of them. Since there are a limited number of responses you can
make, Info allows you to abbreviate what you type, only typing as much
of the response as is necessary to uniquely identify it. In addition,
you can request Info to fill in as much of the response as is possible;
this is called "completion".
The following commands are available when completing in the echo
area:
`TAB' (`echo-area-complete')
`SPC'
Inserts as much of a completion as is possible.
`?' (`echo-area-possible-completions')
Displays a window containing a list of the possible completions of
what you have typed so far. For example, if the available choices
are:
bar
foliate
food
forget
and you have typed an `f', followed by `?', the possible
completions would contain:
foliate
food
forget
i.e., all of the choices which begin with `f'. Pressing SPC or
TAB would result in `fo' appearing in the echo area, since all of
the choices which begin with `f' continue with `o'. Now, typing
`l' followed by `TAB' results in `foliate' appearing in the echo
area, since that is the only choice which begins with `fol'.
`ESC C-v' (`echo-area-scroll-completions-window')
Scrolls the completions window, if that is visible, or the "other"
window if not.
File: octave.info, Node: Printing Nodes, Next: Other Info Commands, Prev: Window Commands, Up: Using Info
Printing Out Nodes
==================
You may wish to print out the contents of a node as a quick
reference document for later use. Info provides you with a command for
doing this. In general, we recommend that you use TeX to format the
document and print sections of it, by running `tex' on the texinfo
source file.
`M-x print-node'
Pipes the contents of the current node through the command in the
environment variable `INFO_PRINT_COMMAND'. If the variable doesn't
exist, the node is simply piped to `lpr'.
File: octave.info, Node: Other Info Commands, Next: Info Variables, Prev: Printing Nodes, Up: Using Info
Miscellaneous Info Commands
===========================
GNU Info contains several commands which self-document GNU Info:
`M-x describe-command'
Reads the name of an Info command in the echo area and then
displays a brief description of what that command does.
`M-x describe-key'
Reads a key sequence in the echo area, and then displays the name
and documentation of the Info command that the key sequence
invokes.
`M-x describe-variable'
Reads the name of a variable in the echo area and then displays a
brief description of what the variable affects.
`M-x where-is'
Reads the name of an Info command in the echo area, and then
displays a key sequence which can be typed in order to invoke that
command.
`C-h' (`get-help-window')
Creates (or moves into) the window displaying `*Help*', and places
a node containing a quick reference card into it. This window
displays the most concise information about GNU Info available.
`h' (`get-info-help-node')
Tries hard to visit the node `(info)Help'. The info file
`info.texi' distributed with GNU Info contains this node. Of
course, the file must first be processed with `makeinfo', and then
placed into the location of your info directory.
Here are the commands for creating a numeric argument:
`C-u' (`universal-argument')
Starts (or multiplies by 4) the current numeric argument. `C-u' is
a good way to give a small numeric argument to cursor movement or
scrolling commands; `C-u C-v' scrolls the screen 4 lines, while
`C-u C-u C-n' moves the cursor down 16 lines.
`M-1' (`add-digit-to-numeric-arg')
`M-2' ... `M-9'
Adds the digit value of the invoking key to the current numeric
argument. Once Info is reading a numeric argument, you may just
type the digits of the argument, without the Meta prefix. For
example, you might give `C-l' a numeric argument of 32 by typing:
`C-u 3 2 C-l'
or
`M-3 2 C-l'
`C-g' is used to abort the reading of a multi-character key
sequence, to cancel lengthy operations (such as multi-file searches) and
to cancel reading input in the echo area.
`C-g' (`abort-key')
Cancels current operation.
The `q' command of Info simply quits running Info.
`q' (`quit')
Exits GNU Info.
If the operating system tells GNU Info that the screen is 60 lines
tall, and it is actually only 40 lines tall, here is a way to tell Info
that the operating system is correct.
`M-x set-screen-height'
Reads a height value in the echo area and sets the height of the
displayed screen to that value.
Finally, Info provides a convenient way to display footnotes which
might be associated with the current node that you are viewing:
`ESC C-f' (`show-footnotes')
Shows the footnotes (if any) associated with the current node in
another window. You can have Info automatically display the
footnotes associated with a node when the node is selected by
setting the variable `automatic-footnotes'. *Note
`automatic-footnotes': Info Variables.
File: octave.info, Node: Info Variables, Prev: Other Info Commands, Up: Using Info
Manipulating Variables
======================
GNU Info contains several "variables" whose values are looked at by
various Info commands. You can change the values of these variables,
and thus change the behavior of Info to more closely match your
environment and info file reading manner.
`M-x set-variable'
Reads the name of a variable, and the value for it, in the echo
area and then sets the variable to that value. Completion is
available when reading the variable name; often, completion is
available when reading the value to give to the variable, but that
depends on the variable itself. If a variable does *not* supply
multiple choices to complete over, it expects a numeric value.
`M-x describe-variable'
Reads the name of a variable in the echo area and then displays a
brief description of what the variable affects.
Here is a list of the variables that you can set in Info.
`automatic-footnotes'
When set to `On', footnotes appear and disappear automatically.
This variable is `On' by default. When a node is selected, a
window containing the footnotes which appear in that node is
created, and the footnotes are displayed within the new window.
The window that Info creates to contain the footnotes is called
`*Footnotes*'. If a node is selected which contains no footnotes,
and a `*Footnotes*' window is on the screen, the `*Footnotes*'
window is deleted. Footnote windows created in this fashion are
not automatically tiled so that they can use as little of the
display as is possible.
`automatic-tiling'
When set to `On', creating or deleting a window resizes other
windows. This variable is `Off' by default. Normally, typing
`C-x 2' divides the current window into two equal parts. When
`automatic-tiling' is set to `On', all of the windows are resized
automatically, keeping an equal number of lines visible in each
window. There are exceptions to the automatic tiling;
specifically, the windows `*Completions*' and `*Footnotes*' are
*not* resized through automatic tiling; they remain their original
size.
`visible-bell'
When set to `On', GNU Info attempts to flash the screen instead of
ringing the bell. This variable is `Off' by default. Of course,
Info can only flash the screen if the terminal allows it; in the
case that the terminal does not allow it, the setting of this
variable has no effect. However, you can make Info perform
quietly by setting the `errors-ring-bell' variable to `Off'.
`errors-ring-bell'
When set to `On', errors cause the bell to ring. The default
setting of this variable is `On'.
`gc-compressed-files'
When set to `On', Info garbage collects files which had to be
uncompressed. The default value of this variable is `Off'.
Whenever a node is visited in Info, the info file containing that
node is read into core, and Info reads information about the tags
and nodes contained in that file. Once the tags information is
read by Info, it is never forgotten. However, the actual text of
the nodes does not need to remain in core unless a particular info
window needs it. For non-compressed files, the text of the nodes
does not remain in core when it is no longer in use. But
de-compressing a file can be a time consuming operation, and so
Info tries hard not to do it twice. `gc-compressed-files' tells
Info it is okay to garbage collect the text of the nodes of a file
which was compressed on disk.
`show-index-match'
When set to `On', the portion of the matched search string is
highlighted in the message which explains where the matched search
string was found. The default value of this variable is `On'.
When Info displays the location where an index match was found,
(*note `next-index-match': Searching Commands.), the portion of the
string that you had typed is highlighted by displaying it in the
inverse case from its surrounding characters.
`scroll-behaviour'
Controls what happens when forward scrolling is requested at the
end of a node, or when backward scrolling is requested at the
beginning of a node. The default value for this variable is
`Continuous'. There are three possible values for this variable:
`Continuous'
Tries to get the first item in this node's menu, or failing
that, the `Next' node, or failing that, the `Next' of the
`Up'. This behavior is identical to using the `]'
(`global-next-node') and `[' (`global-prev-node') commands.
`Next Only'
Only tries to get the `Next' node.
`Page Only'
Simply gives up, changing nothing. If `scroll-behaviour' is
`Page Only', no scrolling command can change the node that is
being viewed.
`scroll-step'
The number of lines to scroll when the cursor moves out of the
window. Scrolling happens automatically if the cursor has moved
out of the visible portion of the node text when it is time to
display. Usually the scrolling is done so as to put the cursor on
the center line of the current window. However, if the variable
`scroll-step' has a nonzero value, Info attempts to scroll the
node text by that many lines; if that is enough to bring the
cursor back into the window, that is what is done. The default
value of this variable is 0, thus placing the cursor (and the text
it is attached to) in the center of the window. Setting this
variable to 1 causes a kind of "smooth scrolling" which some
people prefer.
`ISO-Latin'
When set to `On', Info accepts and displays ISO Latin characters.
By default, Info assumes an ASCII character set. `ISO-Latin' tells
Info that it is running in an environment where the European
standard character set is in use, and allows you to input such
characters to Info, as well as display them.
File: octave.info, Node: Concept Index, Next: Variable Index, Prev: Using Info, Up: Top
Concept Index
*************
* Menu:
* -debug: Command Line Options.
* -echo-commands: Command Line Options.
* -help: Command Line Options.
* -ignore-init-file: Command Line Options.
* -info-file FILENAME: Command Line Options.
* -interactive: Command Line Options.
* -norc: Command Line Options.
* -path PATH: Command Line Options.
* -quiet: Command Line Options.
* -silent: Command Line Options.
* -verbose: Command Line Options.
* -version: Command Line Options.
* -?: Command Line Options.
* -d: Command Line Options.
* -f: Command Line Options.
* -h: Command Line Options.
* -i: Command Line Options.
* -p PATH: Command Line Options.
* -q: Command Line Options.
* -v: Command Line Options.
* -V: Command Line Options.
* -x: Command Line Options.
* ...: Variable-length Return Lists.
* ...: Variable-length Argument Lists.
* ... continuation marker: The unwind_protect Statement.
* break statement: The break Statement.
* continue statement: The continue Statement.
* elseif statement: The if Statement.
* else statement: The if Statement.
* endfor statement: The for Statement.
* endif statement: The if Statement.
* endwhile statement: The while Statement.
* end statement: Statements.
* for statement: The for Statement.
* if statement: The if Statement.
* while statement: The while Statement.
* \ continuation marker: The unwind_protect Statement.
* #!: Executable Octave Programs.
* #: Comments.
* %: Comments.
* acknowledgements: Preface.
* addition: Arithmetic Ops.
* amusements: Miscellaneous Utilities.
* and operator: Boolean Expressions.
* answers, incorrect: Bug Criteria.
* answers, incorrect: Bug Reporting.
* arguments in function call: Calling Functions.
* arithmetic operators: Arithmetic Ops.
* assignment expressions: Assignment Ops.
* assignment operators: Assignment Ops.
* body of a loop: The while Statement.
* boolean expressions: Boolean Expressions.
* boolean operators: Boolean Expressions.
* bug criteria: Bug Criteria.
* bug report mailing lists: Bug Lists.
* bugs: Reporting Bugs.
* bugs, investigating: Bug Reporting.
* bugs, known: Trouble.
* bugs, reporting: Bug Reporting.
* bugs, reporting: Bug Lists.
* built-in variables: Built-in Variables.
* character strings: String Constants.
* command options: Command Line Options.
* comments: Comments.
* comparison expressions: Comparison Ops.
* complex-conjugate transpose: Arithmetic Ops.
* continuation lines: The unwind_protect Statement.
* contributors: Preface.
* conversion specifications (printf): Formatted Output.
* conversion specifications (scanf): Formatted Input.
* copyright: Preface.
* core dump: Bug Criteria.
* DAE: Differential Equations.
* data structures: Data Structures.
* decrement operator: Assignment Ops.
* defining functions: Functions and Scripts.
* Differential Equations: Differential Equations.
* diffs, submitting: Sending Patches.
* division: Arithmetic Ops.
* documenting Octave programs: Comments.
* element-by-element evaluation: Element-by-element Boolean Operators.
* equality operator: Comparison Ops.
* equality, tests for: Comparison Ops.
* equations, nonlinear: Nonlinear Equations.
* erroneous messages: Bug Criteria.
* erroneous results: Bug Reporting.
* erroneous results: Bug Criteria.
* error messages, incorrect: Bug Criteria.
* escape sequence notation: String Constants.
* executable scripts: Executable Octave Programs.
* exiting octave: Running Octave.
* exponentiation: Arithmetic Ops.
* expression, range: Ranges.
* expressions: Expressions.
* expressions, assignment: Assignment Ops.
* expressions, boolean: Boolean Expressions.
* expressions, comparison: Comparison Ops.
* expressions, logical: Boolean Expressions.
* factorial function: Recursion.
* fatal signal: Bug Criteria.
* flag character (printf): Output Conversion Syntax.
* flag character (scanf): Input Conversion Syntax.
* flying high and fast: Variables.
* Fordyce, A. P.: Evaluating Strings as Commands.
* function file: Function Files.
* functions, user-defined: Functions and Scripts.
* getting a good job: Variables.
* graphics: Two-Dimensional Plotting.
* greater than operator: Comparison Ops.
* help, where to find: Service.
* Hermitian operator: Arithmetic Ops.
* history: Preface.
* improving Octave: Bug Criteria.
* improving Octave: Sending Patches.
* incorrect error messages: Bug Criteria.
* incorrect output: Bug Reporting.
* incorrect output: Bug Criteria.
* incorrect results: Bug Criteria.
* incorrect results: Bug Reporting.
* increment operator: Assignment Ops.
* initialization: Startup Files.
* input conversions, for scanf: Table of Input Conversions.
* installation trouble: Trouble.
* installing Octave: Installation.
* introduction: Introduction.
* invalid input: Bug Criteria.
* job hunting: Variables.
* keywords: Keywords.
* known causes of trouble: Trouble.
* less than operator: Comparison Ops.
* logical expressions: Boolean Expressions.
* logical operators: Boolean Expressions.
* loop: The while Statement.
* lottery numbers: Amusements.
* LP: Optimization.
* lvalue: Assignment Ops.
* matching failure, in scanf: Formatted Input.
* matrices: Matrices.
* matrix multiplication: Arithmetic Ops.
* maximum field width (scanf): Input Conversion Syntax.
* minimum field width (printf): Output Conversion Syntax.
* multiplication: Arithmetic Ops.
* negation: Arithmetic Ops.
* NLP: Optimization.
* nonlinear equations: Nonlinear Equations.
* nonlinear programming: Optimization.
* not operator: Boolean Expressions.
* numbers, lottery: Amusements.
* numbers, prime: Amusements.
* numeric constant: Numeric Constants.
* numeric value: Numeric Constants.
* Octave command options: Command Line Options.
* ODE: Differential Equations.
* operator precedence: Increment Ops.
* operators, arithmetic: Arithmetic Ops.
* operators, assignment: Assignment Ops.
* operators, boolean: Boolean Expressions.
* operators, decrement: Assignment Ops.
* operators, increment: Assignment Ops.
* operators, logical: Boolean Expressions.
* operators, relational: Comparison Ops.
* optimization: Optimization.
* options, Octave command: Command Line Options.
* or operator: Boolean Expressions.
* output conversions, for printf: Table of Output Conversions.
* patches, submitting: Sending Patches.
* plotting: Two-Dimensional Plotting.
* precision (printf): Output Conversion Syntax.
* prime numbers: Amusements.
* program, self contained: Executable Octave Programs.
* programs, documenting: Comments.
* QP: Optimization.
* quadratic programming: Optimization.
* quitting octave: Running Octave.
* quotient: Arithmetic Ops.
* range expressions: Ranges.
* relational operators: Comparison Ops.
* reporting bugs: Bug Lists.
* reporting bugs: Reporting Bugs.
* results, incorrect: Bug Reporting.
* results, incorrect: Bug Criteria.
* script files: Functions and Scripts.
* scripts, executable: Executable Octave Programs.
* self contained programs: Executable Octave Programs.
* short-circuit evaluation: Short-circuit Boolean Operators.
* side effect: Assignment Ops.
* startup: Startup Files.
* statements: Statements.
* strings: Rearranging Matrices.
* strings: String Constants.
* structures: Data Structures.
* submitting diffs: Sending Patches.
* submitting patches: Sending Patches.
* subtraction: Arithmetic Ops.
* suggestions: Bug Criteria.
* tests for equality: Comparison Ops.
* transpose: Arithmetic Ops.
* transpose, complex-conjugate: Arithmetic Ops.
* troubleshooting: Trouble.
* unary minus: Arithmetic Ops.
* undefined behavior: Bug Criteria.
* undefined function value: Bug Criteria.
* use of comments: Comments.
* user-defined functions: Functions and Scripts.
* user-defined variables: Variables.
* Variable-length argument lists: Variable-length Argument Lists.
* Variable-length return lists: Variable-length Return Lists.
* variables: Built-in Variables.
* variables, built-in: Built-in Variables.
* variables, user-defined: Variables.
* warranty: Preface.
* wrong answers: Bug Criteria.
* wrong answers: Bug Reporting.
File: octave.info, Node: Variable Index, Next: Function Index, Prev: Concept Index, Up: Top
Variable Index
**************
* Menu:
* ans: Other Built-in Variables.
* automatic_replot: Two-Dimensional Plotting.
* automatic_replot: User Preferences.
* default_return_value: User Preferences.
* default_save_format: Basic Input and Output.
* default_save_format: User Preferences.
* define_all_return_values: User Preferences.
* do_fortran_indexing: User Preferences.
* EDITOR: User Preferences.
* empty_list_elements_ok: User Preferences.
* eps: Predefined Constants.
* gnuplot_binary: User Preferences.
* I, i, J, j: Predefined Constants.
* ignore_function_time_stamp: User Preferences.
* IMAGEPATH: User Preferences.
* implicit_str_to_num_ok: User Preferences.
* Inf, inf: Predefined Constants.
* INFO_FILE: User Preferences.
* LOADPATH: User Preferences.
* NaN, nan: Predefined Constants.
* nargout: Defining Functions.
* OCTAVE_VERSION: User Preferences.
* ok_to_lose_imaginary_part: User Preferences.
* output_max_field_width: User Preferences.
* output_precision: User Preferences.
* PAGER: User Preferences.
* page_screen_output: User Preferences.
* pi: Predefined Constants.
* prefer_column_vectors: User Preferences.
* prefer_zero_one_indexing: User Preferences.
* print_answer_id_name: User Preferences.
* print_empty_dimensions: User Preferences.
* propagate_empty_matrices: User Preferences.
* PS1: User Preferences.
* PS2: User Preferences.
* PS4: User Preferences.
* PWD: Other Built-in Variables.
* realmax: Predefined Constants.
* realmin: Predefined Constants.
* resize_on_range_error: User Preferences.
* return_last_computed_value: User Preferences.
* save_precision: User Preferences.
* save_precision: Basic Input and Output.
* SEEK_CUR: Predefined Constants.
* SEEK_END: Predefined Constants.
* SEEK_SET: Predefined Constants.
* silent_functions: User Preferences.
* split_long_rows: User Preferences.
* stderr: Predefined Constants.
* stdin: Predefined Constants.
* stdout: Predefined Constants.
* suppress_verbose_help_message: User Preferences.
* treat_neg_dim_as_zero: User Preferences.
* warn_assign_as_truth_value: User Preferences.
* warn_comma_in_global_decl: User Preferences.
* warn_divide_by_zero: User Preferences.
* warn_function_name_clash: User Preferences.
* whitespace_in_literal_matrix: User Preferences.