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% This file is TeX source for a reference card describing Octave.
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% Copyright (C) 1996-2013 John W. Eaton
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% This file is part of Octave.
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% Octave is free software; you can redistribute it and/or modify it
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% under the terms of the GNU General Public License as published by the
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% Free Software Foundation; either version 3 of the License, or (at your
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% option) any later version.
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% Octave is distributed in the hope that it will be useful, but WITHOUT
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% ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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% FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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% You should have received a copy of the GNU General Public License
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% along with Octave; see the file COPYING. If not, see
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% <http://www.gnu.org/licenses/>.
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% Heavily modified by jwe from the source for the gdb reference card,
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% which was orignally written by Roland Pesch <pesch@cygnus.com>.
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% Copyright (C) 1991, 1992 Free Software Foundation, Inc.
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% Permission is granted to make and distribute verbatim copies of
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% this reference provided the copyright notices and permission notices
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% are preserved on all copies.
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% TeX markup is a programming language; accordingly this file is source
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% for a program to generate a reference.
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% You only have to set the total width and height of the paper, the
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% horizontal and vertical margin space measured from *paper edge*
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% and the interline and interspec spacing.
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% In order to support a new papersize, you have to fiddle with the
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% latter four dimensions. Just try out a few values.
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% All other values will be computed at process time so it should be
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% quite easy to support different paper sizes - only four values to
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% To find the configuration places, just search for the string
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% "User configuration".
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% -- Andreas Vogel (av@ssw.de)
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% NOTE ON INTENTIONAL OMISSIONS: This reference card includes many
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% Octave commands, but due to space constraints there are some things
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% I chose to omit. In general, not all synonyms for commands are
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% covered, nor all variations of a command.
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\def\octaveversion{3.0.0}
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\def\refcardedition{2.0}
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% Declarations (these must come first)
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\newdimen\intersecwidth
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\newcount\columnsperpage
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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% There are currently 8 total columns, so some of these options will
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% not create a single page reference card.
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% Choose a paper size. Default is US letter size.
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\def\refcardafoursize{a4} % 3 columns, A4 paper (1 in = 254 mm)
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\def\refcardlegalsize{legal} % 4 columns, US legal paper (8.5 x 14in)
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\def\refcardlettersize{letter} % 3 columns, US letter paper (8.5 x 11in)
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\ifx\refcardsize\refcardafoursize
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\columnsperpage=3 % total number of columns to typeset
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\totalwidth=297mm % total width of paper
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\totalheight=210mm % total height of paper
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\hmargin=9mm % horizontal margin width
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\vmargin=7mm % vertical margin width
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\secskip=3mm % space between refcard secs
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\lskip=0.4mm % extra skip between \sec entries
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\ifx\refcardsize\refcardlegalsize
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\columnsperpage=4 % total number of columns to typeset
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\totalwidth=14in % total width of paper
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\totalheight=8.5in % total height of paper
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\hmargin=0.20in % horizontal margin width
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\vmargin=0.25in % vertical margin width
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\secskip=0.75pc % space between refcard secs
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\lskip=2pt % extra skip between \sec entries
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\columnsperpage=3 % total number of columns to typeset
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\totalwidth=11in % total width of paper
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\totalheight=8.5in % total height of paper
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\hmargin=0.25in % horizontal margin width
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\vmargin=0.25in % vertical margin width
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\secskip=0.75pc % space between refcard secs
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\lskip=2pt % extra skip between \sec entries
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\ifx\pdfoutput\undefined
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\pdfpageheight=\totalheight
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\pdfpagewidth=\totalwidth
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% Change according to personal taste, not papersize dependent.
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\barwidth=.1pt % width of the cropmark bar
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\barheight=2pt % height of the cropmark bar
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\intersecwidth=0.5em % width between \itmwid and \dfnwid
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% Uncomment only one of the following definitions for folding guides.
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% No printed folding guide:
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%\def\vdecor{\hskip\hmargin plus1fil
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% \hskip\barwidth plus1fil
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% \hskip\hmargin plus1fil}
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% Solid line folding guide:
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%\def\vdecor{\hskip\hmargin plus1fil%
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% \vrule width \barwidth%
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% \hskip\hmargin plus1fil}
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% For small marks near top and bottom as folding guide:
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\def\vdecor{\hskip\hmargin plus1fil%
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\vbox to \vsize{\hbox to \barwidth{\vrule height\barheight width\barwidth}%
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\hbox to \barwidth{\vrule height\barheight width\barwidth}}%
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\hskip\hmargin plus1fil}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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% END CONFIGURATION %
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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% values to be computed based on above definitions.
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% nothing to configure
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\newdimen\fullhsize % width of area without margins
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\newdimen\itmwid % width of item column
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\newdimen\dfnwid % width of definition column
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\newdimen\idnwid % width of indented text
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\newdimen\temp % only for temporary use
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% an alternate section format, used in some cases to make text fit better.
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\newdimen\altitmwid % width of item column in altsec
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\newdimen\altdfnwid % width of definition column in altsec
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% Subtract hmargin for left and right sides of paper from full width.
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% fullhsize = totalwidth - (2 * hmargin)
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\fullhsize=\totalwidth
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\advance \fullhsize by -\temp
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% intercolumn space is composed of hmargin barwidth hmargin so that we
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% get the same amount of space on either side of the (optional) rule
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% between columns. For N columns, we need to subtract this amount of
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% space N-1 times. Divide by the number of columns to get the final
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% value of \hsize that we use to typeset columns.
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% hsize = (fullhsize - (ncols-1)*barwidth - 2*(ncols-1)*hmargin) / ncols
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\tmpcnt\columnsperpage
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\advance \tmpcnt by -1
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\multiply \temp by \tmpcnt
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\advance \hsize by -\temp
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\multiply \tmpcnt by 2
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\multiply \temp by \tmpcnt
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\advance \hsize by -\temp
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\divide \hsize by \columnsperpage
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% Vertical size is easy -- same amount of space above and below.
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% vsize = totalheight - (2 * vmargin)
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\advance \vsize by -\temp
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% adjust the offsets so the margins are measured *from paper edge*
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\hoffset=-1in \advance \hoffset by \hmargin
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\voffset=-1in \advance \voffset by \vmargin
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% Width of items in a section.
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% itmwid = (hsize - intersecwidth) * 1/3
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% dfnwid = (hsize - intersecwidth) * 2/3
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\advance \temp by -\intersecwidth
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% width of the corresponding definition
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\advance \dfnwid by -\itmwid
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% indentation for sub items, etc.
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\temp=\hsize \advance\temp by -1em
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% Width of items in an alt section.
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\altitmwid=\itmwid \advance \altitmwid by 0.35in
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\altdfnwid=\dfnwid \advance \altdfnwid by -0.35in
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% * set each column in a box
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% * append new columns in a global `holding' box, inserting
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% intercolumn decorations as necessary.
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% * when we fill a page, dump the saved box and the latest column,
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% separated by the intercolumn decoration.
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\global\advance\colno by 1
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\global\setbox\holdbox=\columnbox
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\ifnum\colno=\columnsperpage
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\shipout\hbox to \fullhsize{\box\holdbox\vdecor\columnbox}
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\global\setbox\holdbox=\vbox{\hbox{\box\holdbox\vdecor\columnbox}}
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\def\columnbox{\leftline{\pagebody}}
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\if R\lcr \null\vfill\eject \fi
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% We can afford to allow some slop
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\normalbaselineskip=9pt
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\footline={\vbox to0pt{\hss}}
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\def\ctl#1{{\tt C-#1}}
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\def\opt#1{{\brm[{\rm #1}]}}
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\def\xtra#1{\noalign{\smallskip{\tt#1}}}
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\long\def\sec#1;#2\endsec{\vskip \secskip
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% column 1 (of halign):
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\vtop{\hsize=\itmwid\tt ##\par\vskip \lskip }\hfil
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% column 2 (of halign):
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\hangindent=\intersecwidth
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\rm ##\par\vskip \lskip}\cr
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% Tail of \long\def fills in halign body with \sec args:
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\long\def\widesec#1;#2\endsec{\vskip \secskip
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% column 1 (of halign):
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##\par\vskip \lskip }\cr
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% Tail of \long\def fills in halign body with \sec args:
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\noalign{{\bbf #1}\vskip 3\lskip}
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% an alternate section format, used in some cases to make text fit better.
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\long\def\altsec#1;#2\endsec{\vskip \secskip
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% column 1 (of halign):
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\vtop{\hsize=\altitmwid\tt
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##\par\vskip \lskip}\hfil
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% column 2 (of halign):
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\hangindent=\intersecwidth
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\rm ##\par\vskip \lskip}\cr
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% Tail of \long\def fills in halign body with \sec args:
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\noalign{{\bbf #1}\vskip \lskip}
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% -------------------------------------
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% The actual text of the reference card
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% -------------------------------------
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{\vbbf Octave Quick Reference}\hfil{\smrm Octave Version \octaveversion}\qquad
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\sec Starting Octave;
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octave&start interactive Octave session\cr
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octave {\it file}&run Octave on commands in {\it file}\cr
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octave --eval {\it code}&Evaluate {\it code} using Octave\cr
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octave --help&describe command line options\cr
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\sec Stopping Octave;
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quit {\rm or} exit&exit Octave\cr
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INTERRUPT&({\it e.g.} \ctl{c}) terminate current command and return to
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help&list all commands and built-in variables\cr
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help {\it command}&briefly describe {\it command}\cr
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doc&use Info to browse Octave manual\cr
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doc {\it command}&search for {\it command} in Octave manual\cr
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lookfor {\it str}&search for {\it command} based on {\it str}\cr
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SPC {\rm or} C-v&scroll forward one screenful\cr
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DEL {\rm or} M-v&scroll backward one screenful\cr
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C-l&redraw the display\cr
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\sec Node Selection in Info;
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n&select the next node\cr
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p&select the previous node\cr
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u&select the `up' node\cr
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t&select the `top' node\cr
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d&select the directory node\cr
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<&select the first node in the current file\cr
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>&select the last node in the current file\cr
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% ]&move forward through the node structure\cr
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% [&move backward through the nodes\cr
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g&reads the name of a node and selects it\cr
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C-x k&kills the current node\cr
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\sec Searching in Info;
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s&search for a string\cr
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C-s&search forward incrementally\cr
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C-r&search backward incrementally\cr
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i&search index \& go to corresponding node\cr
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,&go to next match from last `i' command\cr
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\sec Command-Line Cursor Motion;
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C-b&move back one character\cr
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C-f&move forward one character\cr
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C-a&move to the start of the line\cr
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C-e&move to the end of the line\cr
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M-f&move forward a word\cr
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M-b&move backward a word\cr
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C-l&clear screen, reprinting current line at top\cr
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\sec Inserting or Changing Text;
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M-TAB&insert a tab character\cr
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DEL&delete character to the left of the cursor\cr
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C-d&delete character under the cursor\cr
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C-v&add the next character verbatim\cr
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C-t&transpose characters at the point\cr
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M-t&transpose words at the point\cr
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% M-u&uppercase the current word\cr
445
% M-l&lowercase the current word\cr
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% M-c&capitalize the current word\cr
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\line{\smrm \opt{ } surround optional arguments
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\hfill ... show one or more arguments}
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\vskip0.25\baselineskip
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\sec Killing and Yanking;
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C-k&kill to the end of the line\cr
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C-y&yank the most recently killed text\cr
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M-d&kill to the end of the current word\cr
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M-DEL&kill the word behind the cursor\cr
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M-y&rotate the kill ring and yank the new top\cr
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\sec Command Completion and History;
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TAB&complete a command or variable name\cr
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M-?&list possible completions\cr
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RET&enter the current line \cr
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C-p&move `up' through the history list\cr
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C-n&move `down' through the history list\cr
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M-<&move to the first line in the history\cr
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M->&move to the last line in the history\cr
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C-r&search backward in the history list\cr
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C-s&search forward in the history list\cr
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history \opt{{-q}} \opt{{\it N\/}}&list {\it N\/} previous history lines,
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omitting history numbers if {\tt -q}\cr
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history -w \opt{{\it file}}&write history to {\it file\/} ({\tt
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\char'0176/.octave\_hist} if no {\it file\/} argument)\cr
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history -r \opt{{\it file}}&read history from {\it file\/} ({\tt
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\char'0176/.octave\_hist} if no {\it file\/} argument)\cr
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edit\_history {\it lines}&edit and then run previous
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commands from the history list\cr
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run\_history {\it lines}&run previous commands from the
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\quad\opt{{\it beg\/}} \opt{{\it end\/}}&Specify the first and last
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history commands to edit or run.\cr
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\omit\hfill\vbox{\hsize=\idnwid\rm\vskip0.25ex
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If {\it beg}\/ is greater than {\it end},
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reverse the list of commands before editing. If {\it end\/} is
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omitted, select commands from {\it beg\/} to the end of the history
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list. If both arguments are omitted, edit the previous item in the
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history list.}\span\cr
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cd {\it dir}&change working directory to {\it dir}\cr
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pwd&print working directory\cr
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ls \opt{{\it options}}&print directory listing\cr
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getenv ({\it string})&return value of named environment variable\cr
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system ({\it cmd})&execute arbitrary shell command string\cr
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\omit\vbox{\rm\vskip0.25ex
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Square brackets delimit literal matrices. Commas separate elements
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on the same row. Semicolons separate rows. Commas may be replaced
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by spaces, and semicolons may be replaced by one or more newlines.
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Elements of a matrix may be arbitrary expressions, assuming
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all the dimensions agree.\vskip0.75ex}\span\cr
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[ {\it x}, {\it y}, ... ]&enter a row vector\cr
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[ {\it x}; {\it y}; ... ]&enter a column vector\cr
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[ {\it w}, {\it x}; {\it y}, {\it z} ]&enter a 2$\times$2 matrix\cr
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\sec Multi-dimensional Arrays;
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\omit\vbox{\rm\vskip0.25ex
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Multi-dimensional arrays may be created with the {\it cat} or
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{\it reshape} commands from two-dimensional sub-matrices.
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\vskip0.75ex}\span\cr
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squeeze ({\it arr})&remove singleton dimensions of the array.\cr
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ndims ({\it arr})&number of dimensions in the array.\cr
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permute ({\it arr}, {\it p})&permute the dimensions of an array.\cr
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ipermute ({\it arr}, {\it p})&array inverse permutation.\cr
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shiftdim ({\it arr}, {\it s})&rotate the array dimensions.\cr
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circshift ({\it arr}, {\it s})&rotate the array elements.\cr
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\sec Sparse Matrices;
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sparse (...)&create a sparse matrix.\cr
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speye ({\it n)}&create sparse identity matrix.\cr
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sprand ({\it n}, {\it m}, {\it d})&sparse rand matrix of density {\it d}.\cr
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spdiags (...)&sparse generalization of {\it diag}.\cr
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nnz ({\it s})&No. non-zero elements in sparse matrix.\cr
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{\it base} : {\it limit}\cr
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{\it base} : {\it incr} : {\it limit}\cr
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\omit\hfill\vbox{\hsize=\idnwid\rm\vskip0.75ex
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Specify a range of values beginning with {\it base\/} with no elements
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greater than {\it limit}. If it is omitted, the default value of
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{\it incr\/} is 1. Negative increments are permitted.}\span\cr
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\sec Strings and Common Escape Sequences;
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\omit\vbox{\rm\vskip0.5ex
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A {\it string constant\/} consists of a sequence of characters
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enclosed in either double-quote or single-quote marks. Strings
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in double-quotes allow the use of the escape sequences below.
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\vskip0.75ex}\span\cr
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\char'134\char'134&a literal backslash\cr
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\char'134 "&a literal double-quote character\cr
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\char'134 '&a literal single-quote character\cr
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\char'134 n&newline, ASCII code 10\cr
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\char'134 t&horizontal tab, ASCII code 9\cr
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\sec Index Expressions;
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{\it var} ({\it idx})&select elements of a vector\cr
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{\it var} ({\it idx1}, {\it idx2})&select elements of a matrix\cr
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\quad {\it scalar}&select row (column) corresponding to {\it scalar}\cr
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\quad {\it vector}&select rows (columns) corresponding to the elements
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\quad {\it range}&select rows (columns) corresponding to the elements
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\quad :&select all rows (columns)\cr
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\sec Global and Persistent Variables;
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global {\it var1} ...&Declare variables global.\cr
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global {\it var1} = {\it val}&Declare variable global. Set initial value.\cr
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persistent {\it var1}&Declare a variable as static to a function.\cr
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persistent {\it var1} = {\it val}&Declare a variable as static to a
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function and set its initial value.\cr
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\omit\hfill\vbox{\rm\vskip0.25ex
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Global variables may be accessed inside the body of a function
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without having to be passed in the function parameter list provided
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they are declared global when used.}\span\cr
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\sec Selected Built-in Functions;
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EDITOR&editor to use with {\tt edit\_history}\cr
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Inf, NaN&IEEE infinity, NaN\cr
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PAGER&program to use to paginate output\cr
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ans&last result not explicitly assigned\cr
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eps&machine precision\cr
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realmax&maximum representable value\cr
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realmin&minimum representable value\cr
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\centerline{\smrm Copyright 1996, 1997, 2007 John W. Eaton\qquad Permissions on back}
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\sec Assignment Expressions;
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{\it var} = {\it expr}&assign expression to variable\cr
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{\it var} ({\it idx}) = {\it expr}&assign expression to indexed variable\cr
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{\it var} ({\it idx}) = []&delete the indexed elements.\cr
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{\it var} $\{${\it idx}$\}$ = {\it expr}&assign elements of a cell array.\cr
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\sec Arithmetic and Increment Operators;
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{\it x} + {\it y}&addition\cr
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{\it x} - {\it y}&subtraction\cr
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{\it x} * {\it y}&matrix multiplication\cr
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{\it x} .* {\it y}&element by element multiplication\cr
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{\it x} / {\it y}&right division, conceptually equivalent to
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{\tt (inverse~(y')~*~x')'}\cr
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{\it x} ./ {\it y}&element by element right division\cr
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{\it x} \char'134{} {\it y}&left division, conceptually equivalent to
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{\tt inverse~(x)~*~y}\cr
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{\it x} .\char'134{} {\it y}&element by element left division\cr
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{\it x} \char'136{} {\it y}&power operator\cr
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{\it x} .\char'136{} {\it y}&element by element power operator\cr
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- {\it x}&negation\cr
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+ {\it x}&unary plus (a no-op)\cr
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{\it x} '&complex conjugate transpose\cr
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{\it x} .'&transpose\cr
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return {\it new\/} value\cr
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{\it x} ++\quad{\rm(}{\it x} --{\rm)}&increment (decrement),
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return {\it old\/} value\cr
634
\sec Comparison and Boolean Operators;
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\omit \vbox{\rm\vskip0.75ex
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These operators work on an element-by-element basis. Both arguments
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are always evaluated.\vskip0.75ex}\span\cr
638
{\it x} < {\it y}&true if {\it x\/} is less than {\it y}\cr
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{\it x} <= {\it y}&true if {\it x\/} is less than or equal to {\it y}\cr
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{\it x} == {\it y}&true if {\it x\/} is equal to {\it y}\cr
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{\it x} >= {\it y}&true if {\it x\/} is greater than or equal to {\it y}\cr
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{\it x} > {\it y}&true if {\it x\/} is greater than {\it y}\cr
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{\it x} != {\it y}&true if {\it x\/} is not equal to {\it y}\cr
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{\it x} \& {\it y}&true if both {\it x\/} and {\it y\/} are true\cr
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{\it x} | {\it y}&true if at least one of {\it x\/} or {\it y\/} is true\cr
646
! {\it bool}&true if {\it bool\/} is false\cr
649
\sec Short-circuit Boolean Operators;
650
\omit \vbox{\rm\vskip0.75ex
651
Operators evaluate left-to-right. Operands are only evaluated if
652
necessary, stopping once overall truth value can be determined.
653
Operands are converted to scalars using the {\tt all}
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function.\vskip0.75ex}\span\cr
655
{\it x} \&\& {\it y}&true if both {\it x\/} and {\it y\/} are true\cr
656
{\it x} || {\it y}&true if at least one of {\it x\/} or {\it y\/} is true\cr
659
\sec Operator Precedence;
660
\omit \vbox{\rm\vskip0.5ex
661
Table of Octave operators, in order of increasing
662
precedence.\vskip0.75ex}\span\cr
663
;\ \ ,&statement separators\cr
664
=&assignment, groups left to right\cr
665
||\ \ \&\&&logical ``or'' and ``and''\cr
666
|\ \ \&&element-wise ``or'' and ``and''\cr
667
< <= == >= > !=&relational operators\cr
669
+\ \ -&addition and subtraction\cr
670
* / \char'134\ \ .*\ \ ./\ \ .\char'134&multiplication and division\cr
672
+\ \ -\ \ ++\ \ --\ \ !&unary minus, increment, logical ``not''\cr
673
\char'136\ \ .\char'136&exponentiation\cr
678
\sec Paths and Packages;
679
path&display the current Octave function path.\cr
680
pathdef&display the default path.\cr
681
addpath ({\it dir})&add a directory to the path.\cr
682
EXEC\_PATH&manipulate the Octave executable path.\cr
683
pkg list&display installed packages.\cr
684
pkg load {\it pack}&Load an installed package.\cr
687
\sec Cells and Structures;
688
{\it{var}}.{\it{field}} = ...&set a field of a structure.\cr
689
{\it{var}}$\{${\it{idx}}$\}$ = ...&set an element of a cell array.\cr
690
cellfun ({\it f}, {\it c})&apply a function to elements of cell array.\cr
691
fieldnames ({\it s})&returns the fields of a structure.\cr
695
for {\it identifier} = {\it expr} {\it stmt-list} endfor\cr
696
\hfill\vbox{\hsize=\idnwid\rm\vskip0.25ex
697
Execute {\it stmt-list} once for each column of {\it expr}. The
698
variable {\it identifier} is set to the value of the current column
699
during each iteration.}\cr\cr
700
while ({\it condition}) {\it stmt-list} endwhile\cr
701
\hfill\vbox{\hsize=\idnwid\rm\vskip0.25ex
702
Execute {\it stmt-list} while {\it condition} is true.}\cr\cr
703
\hbox{\vtop{\hsize=\itmwid\tt break}
704
\vtop{\hsize=\dfnwid\rm exit innermost loop}}\cr
705
\hbox{\vtop{\hsize=\itmwid\tt continue}
706
\vtop{\hsize=\dfnwid\rm go to beginning of innermost loop}}\cr
707
\hbox{\vtop{\hsize=\itmwid\tt return}
708
\vtop{\hsize=\dfnwid\rm return to calling function}}\cr\cr
709
if ({\it condition}) {\it if-body} \opt{{\tt else} {\it else-body}} endif\cr
710
\hfill\vbox{\hsize=\idnwid\rm\vskip0.25ex
711
Execute {\it if-body} if {\it condition} is true, otherwise execute
713
if ({\it condition}) {\it if-body} \opt{{\tt elseif} ({\it condition})
714
{\it elseif-body}} endif\cr
715
\hfill\vbox{\hsize=\idnwid\rm\vskip0.25ex
716
Execute {\it if-body} if {\it condition} is true, otherwise execute
717
the {\it elseif-body} corresponding to the first {\tt elseif}
718
condition that is true, otherwise execute {\it else-body}.}\cr
719
\hfill\vbox{\hsize=\idnwid\rm\vskip0.25ex
720
Any number of {\tt elseif} clauses may appear in an {\tt if}
722
unwind\_protect {\it body} unwind\_protect\_cleanup {\it cleanup} end\cr
723
\hfill\vbox{\hsize=\idnwid\rm\vskip0.25ex
724
Execute {\it body}. Execute {\it cleanup} no matter how control
725
exits {\it body}.}\cr
726
try {\it body} catch {\it cleanup} end\cr
727
\hfill\vbox{\hsize=\idnwid\rm\vskip0.25ex
728
Execute {\it body}. Execute {\it cleanup} if {\it body} fails.}\cr
732
strcmp ({\it s}, {\it t})&compare strings\cr
733
strcat ({\it s}, {\it t}, ...)&concatenate strings\cr
734
regexp ({\it str}, {\it pat})&strings matching regular expression\cr
735
regexprep ({\it str}, {\it pat}, {\it rep})&Match and replace sub-strings\cr
738
\widesec Defining Functions;
739
function \opt{{\it ret-list}} {\it function-name}
740
\opt{\hskip0.2em({\it arg-list})\hskip0.2em}\cr
741
\quad{\it function-body}\cr
743
{\rm {\it ret-list\/} may be a single identifier or a comma-separated
744
list of identifiers delimited by square-brackets.\vskip0.75ex}\cr
745
{\rm {\it arg-list\/} is a comma-separated list of identifiers and may
751
\sec Function Handles;
752
@{\it{func}}& Define a function handle to {\it func}.\cr
753
@({\it var1}, ...) {\it expr}&Define an anonymous function handle.\cr
754
str2func ({\it str})&Create a function handle from a string.\cr
755
functions ({\it handle})&Return information about a function handle.\cr
756
func2str ({\it handle})&Return a string representation of a
758
{\it handle} ({\it arg1}, ...)&Evaluate a function handle.\cr
759
feval ({\it func}, {\it arg1}, ...)&Evaluate a function handle or
760
string, passing remaining args to {\it func}\cr
761
\omit\vbox{\rm\vskip0.25ex
762
Anonymous function handles take a copy of the variables in the
763
current workspace.\vskip0.75ex}\span\cr
766
\sec Miscellaneous Functions;
767
eval ({\it str})&evaluate {\it str} as a command\cr
768
error ({\it message})&print message and return to top level\cr
769
warning ({\it message})&print a warning message\cr
770
clear {\it pattern}&clear variables matching pattern\cr
771
exist ({\it str})&check existence of variable or function\cr
772
who, whos&list current variables\cr
773
whos {\it var}&details of the variable {\it var}\cr
776
\sec Basic Matrix Manipulations;
777
rows ({\it a})&return number of rows of {\it a}\cr
778
columns ({\it a})&return number of columns of {\it a}\cr
779
all ({\it a})&check if all elements of {\it a\/} nonzero\cr
780
any ({\it a})&check if any elements of {\it a\/} nonzero\cr
784
find ({\it a})&return indices of nonzero elements\cr
785
sort ({\it a})&order elements in each column of {\it a}\cr
786
sum ({\it a})&sum elements in columns of {\it a}\cr
787
prod ({\it a})&product of elements in columns of {\it a}\cr
788
min ({\it args})&find minimum values\cr
789
max ({\it args})&find maximum values\cr
790
rem ({\it x}, {\it y})&find remainder of {\it x}/{\it y}\cr
791
reshape ({\it a}, {\it m}, {\it n})&reformat {\it a} to be {\it m} by
793
diag ({\it v}, {\it k})&create diagonal matrices\cr
794
linspace ({\it b}, {\it l}, {\it n})&create vector of linearly-spaced
796
logspace ({\it b}, {\it l}, {\it n})&create vector of log-spaced
798
eye ({\it n}, {\it m})&create {\it n\/} by {\it m\/} identity matrix\cr
799
ones ({\it n}, {\it m})&create {\it n\/} by {\it m\/} matrix of ones\cr
800
zeros ({\it n}, {\it m})&create {\it n\/} by {\it m\/} matrix of zeros\cr
801
rand ({\it n}, {\it m})&create {\it n\/} by {\it m\/} matrix of random
805
% sin ({\it a}) cos({\it a}) tan({\it a})&trigonometric functions\cr
806
% asin ({\it a}) acos({\it a}) atan({\it a})&inverse trigonometric functions\cr
807
% sinh ({\it a}) cosh({\it a}) tanh({\it a})&hyperbolic trig functions\cr
808
% asinh ({\it a}) acosh({\it a}) atanh({\it a})&inverse hyperbolic trig
812
chol ({\it a})&Cholesky factorization\cr
813
det ({\it a})&compute the determinant of a matrix\cr
814
eig ({\it a})&eigenvalues and eigenvectors\cr
815
expm ({\it a})&compute the exponential of a matrix\cr
816
hess ({\it a})&compute Hessenberg decomposition\cr
817
inverse ({\it a})&invert a square matrix\cr
818
norm ({\it a}, {\it p})&compute the {\it p}-norm of a matrix\cr
819
pinv ({\it a})&compute pseudoinverse of {\it a}\cr
820
qr ({\it a})&compute the QR factorization of a matrix\cr
821
rank ({\it a})&matrix rank\cr
822
sprank ({\it a})&structural matrix rank\cr
823
schur ({\it a})&Schur decomposition of a matrix\cr
824
svd ({\it a})&singular value decomposition\cr
825
syl ({\it a}, {\it b}, {\it c})&solve the Sylvester equation\cr
830
\sec Equations, ODEs, DAEs, Quadrature;
831
*fsolve&solve nonlinear algebraic equations\cr
832
*lsode&integrate nonlinear ODEs\cr
833
*dassl&integrate nonlinear DAEs\cr
834
*quad&integrate nonlinear functions\cr
835
perror ({\it nm}, {\it code})&for functions that return numeric
836
codes, print error message for named function and given error
839
{\tt *} See the on-line or printed manual for the complete list of
840
arguments for these functions.}\span\cr
844
% create\_set ({\it a}, {\it b})&create row vector of unique values\cr
845
% complement ({\it a}, {\it b})&elements of {\it b} not in {\it a}\cr
846
% intersection ({\it a}, {\it b})&intersection of sets {\it a} and {\it b}\cr
847
% union ({\it a}, {\it b})&union of sets {\it a} and {\it b}\cr
850
\sec Signal Processing;
851
fft ({\it a})&Fast Fourier Transform using FFTW\cr
852
ifft ({\it a})&inverse FFT using FFTW\cr
853
freqz ({\it args})&FIR filter frequency response\cr
854
filter ({\it a}, {\it b}, {\it x})&filter by transfer function\cr
855
conv ({\it a}, {\it b})&convolve two vectors\cr
856
hamming ({\it n})&return Hamming window coefficients\cr
857
hanning ({\it n})&return Hanning window coefficients\cr
860
\altsec Image Processing;
861
colormap ({\it map})&set the current colormap\cr
862
gray2ind ({\it i}, {\it n})&convert gray scale to Octave image\cr
863
image ({\it img}, {\it zoom})&display an Octave image matrix\cr
864
imagesc ({\it img}, {\it zoom})&display scaled matrix as image\cr
865
imread ({\it file})&load an image file\cr
866
imshow ({\it img}, {\it map})&display Octave image\cr
867
imshow ({\it i}, {\it n})&display gray scale image\cr
868
imshow ({\it r}, {\it g}, {\it b})&display RGB image\cr
869
imwrite ({\it img}, {\it file})&write images in various file formats\cr
870
ind2gray ({\it img}, {\it map})&convert Octave image to gray scale\cr
871
ind2rgb ({\it img}, {\it map})&convert indexed image to RGB\cr
872
rgb2ind ({\it r}, {\it g}, {\it b})&convert RGB to Octave image\cr
873
save a matrix to {\it file}\span\cr
876
\altsec C-style Input and Output;
877
fopen ({\it name}, {\it mode})&open file {\it name}\cr
878
fclose ({\it file})&close {\it file}\cr
879
printf ({\it fmt}, ...)&formatted output to {\tt stdout}\cr
880
fprintf ({\it file}, {\it fmt}, ...)&formatted output to {\it file}\cr
881
sprintf ({\it fmt}, ...)&formatted output to string\cr
882
scanf ({\it fmt})&formatted input from {\tt stdin}\cr
883
fscanf ({\it file}, {\it fmt})&formatted input from {\it file}\cr
884
sscanf ({\it str}, {\it fmt})&formatted input from {\it string}\cr
885
fgets ({\it file}, {\it len})&read {\it len\/} characters from {\it file\/}\cr
886
fflush ({\it file})&flush pending output to {\it file}\cr
887
ftell ({\it file})&return file pointer position\cr
888
frewind ({\it file})&move file pointer to beginning\cr
889
freport&print a info for open files\cr
890
fread ({\it file}, {\it size}, {\it prec})&read binary data files\cr
891
fwrite ({\it file}, {\it size}, {\it prec})&write binary data files\cr
892
feof ({\it file})&determine if pointer is at EOF\cr
893
\omit \vbox{\rm\vskip0.75ex
894
A file may be referenced either by name or by the number returned
895
from {\tt fopen}. Three files are preconnected when Octave starts:
896
{\tt stdin}, {\tt stdout}, and {\tt stderr}.\vskip0.75ex}\span\cr
899
\sec Other Input and Output functions;
900
save {\it file} {\it var} ...&save variables in {\it file}\cr
901
load {\it file}&load variables from {\it file}\cr
902
disp ({\it var})&display value of {\it var} to screen\cr
908
compan ({\it p})&companion matrix\cr
909
conv ({\it a}, {\it b})&convolution\cr
910
deconv ({\it a}, {\it b})&deconvolve two vectors\cr
911
poly ({\it a})&create polynomial from a matrix\cr
912
polyderiv ({\it p})&derivative of polynomial\cr
913
polyreduce ({\it p})&integral of polynomial\cr
914
polyval ({\it p}, {\it x})&value of polynomial at {\it x}\cr
915
polyvalm ({\it p}, {\it x})&value of polynomial at {\it x}\cr
916
roots ({\it p})&polynomial roots\cr
917
residue ({\it a}, {\it b})&partial fraction expansion of
918
ratio {\it a}/{\it b}\cr
922
corrcoef ({\it x}, {\it y})&correlation coefficient\cr
923
cov ({\it x}, {\it y})&covariance\cr
924
mean ({\it a})&mean value\cr
925
median ({\it a})&median value\cr
926
std ({\it a})&standard deviation\cr
927
var ({\it a})&variance\cr
930
\sec Plotting Functions;
931
plot ({\it args})&2D plot with linear axes\cr
932
plot3 ({\it args})&3D plot with linear axes\cr
933
line ({\it args})&2D or 3D line\cr
934
patch ({\it args})&2D patch\cr
935
semilogx ({\it args})&2D plot with logarithmic x-axis\cr
936
semilogy ({\it args})&2D plot with logarithmic y-axis\cr
937
loglog ({\it args})&2D plot with logarithmic axes\cr
938
bar ({\it args})&plot bar charts\cr
939
stairs ({\it x}, {\it y})&plot stairsteps\cr
940
stem ({\it x}, {\it y})&plot a stem graph\cr
941
hist ({\it y}, {\it x})&plot histograms\cr
942
contour ({\it x}, {\it y}, {\it z})&contour plot\cr
943
title ({\it string})&set plot title\cr
944
axis ({\it limits})&set axis ranges\cr
945
xlabel ({\it string})&set x-axis label\cr
946
ylabel ({\it string})&set y-axis label\cr
947
zlabel ({\it string})&set z-axis label\cr
948
text ({\it x}, {\it y}, {\it str})&add text to a plot\cr
949
legend ({\it string})&set label in plot key\cr
950
grid \opt{on$|$off}&set grid state\cr
951
hold \opt{on$|$off}&set hold state\cr
952
ishold&return 1 if hold is on, 0 otherwise\cr
953
mesh ({\it x}, {\it y}, {\it z})&plot 3D surface\cr
954
meshgrid ({\it x}, {\it y})&create mesh coordinate matrices\cr
957
\vskip 0pt plus 2fill
961
Edition \refcardedition\ for Octave Version \octaveversion. Copyright
962
1996, 2007, John W. Eaton
963
(jwe@octave.org). The author assumes no responsibility for any
966
This card may be freely distributed under the terms of the GNU
967
General Public License.
969
\TeX{} Macros for this card by Roland Pesch (pesch@cygnus.com),
970
originally for the GDB reference card
972
Octave itself is free software; you are welcome to distribute copies of
973
it under the terms of the GNU General Public License. There is
974
absolutely no warranty for Octave.
added
removed
doc/refcard/refcard.tex
