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annotate doc/faq/Octave-FAQ.texi @ 8215:518789a0539d
FAQ entry about split development packages in distributions
| author | Thomas Weber <thomas.weber.mail@gmail.com> |
|---|---|
| date | Tue, 14 Oct 2008 14:34:56 -0400 |
| parents | de8b07e95d1b |
| children | 242756f065f0 |
| rev | line source |
|---|---|
| 7018 | 1 % Copyright (C) 1997, 1998, 1999, 2001, 2003, 2004, 2005, 2007 John W. Eaton |
| 2 % | |
| 3 % This file is part of Octave. | |
| 4 % | |
| 5 % Octave is free software; you can redistribute it and/or modify it | |
| 6 % under the terms of the GNU General Public License as published by the | |
| 7 % Free Software Foundation; either version 3 of the License, or (at | |
| 8 % your option) any later version. | |
| 9 % | |
| 10 % Octave is distributed in the hope that it will be useful, but WITHOUT | |
| 11 % ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| 12 % FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
| 13 % for more details. | |
| 14 % | |
| 15 % You should have received a copy of the GNU General Public License | |
| 16 % along with Octave; see the file COPYING. If not, see | |
| 17 % <http://www.gnu.org/licenses/>. | |
| 18 | |
| 2866 | 19 \input texinfo.tex @c -*-texinfo-*- |
| 20 | |
| 3030 | 21 @setfilename Octave-FAQ.info |
| 2866 | 22 @settitle Frequently asked questions about Octave (with answers) |
| 23 | |
| 24 @setchapternewpage off | |
| 5099 | 25 @direntry |
| 6584 | 26 * Octave-FAQ: (Octave-FAQ). Frequently asked questions about Octave |
| 5099 | 27 @end direntry |
| 2866 | 28 @titlepage |
| 29 @title Octave FAQ | |
| 30 @subtitle Frequently asked questions about Octave | |
| 8128 | 31 @subtitle September 2008 |
| 2866 | 32 @sp 1 |
| 6900 | 33 @author John W. Eaton and David Bateman |
| 2866 | 34 @page |
| 35 @end titlepage | |
| 36 | |
| 5423 | 37 @ifnottex |
| 4830 | 38 @node Top |
| 2866 | 39 @top |
| 40 @unnumbered Preface | |
| 41 @cindex FAQ for Octave, latest version | |
| 5423 | 42 @end ifnottex |
| 2866 | 43 |
| 44 This is a list of frequently asked questions (FAQ) for Octave users. | |
| 45 | |
| 6584 | 46 We are always looking for new questions (@emph{with} answers), better |
| 47 answers, or both. Please send suggestions to @email{bug@@octave.org}. | |
| 48 If you have general questions about Octave, or need help for something | |
| 49 that is not covered by the Octave manual or the FAQ, please use the | |
| 50 @email{help@@octave.org} mailing list. | |
| 2866 | 51 |
| 52 This FAQ is intended to supplement, not replace, the Octave manual. | |
| 6584 | 53 Before posting a question to the @email{help@@octave.org} mailing list, |
| 54 you should first check to see if the topic is covered in the manual. | |
| 2866 | 55 |
| 56 @menu | |
| 6583 | 57 * What is Octave?:: |
| 58 * How can I cite Octave?:: | |
| 8128 | 59 * Series 3.0.N:: |
| 6583 | 60 * Octave Features:: |
| 61 * Learning more about Octave:: | |
| 62 * Getting Octave:: | |
| 63 * Installation:: | |
| 2866 | 64 * Common problems:: |
| 6584 | 65 * How do I ...?:: |
| 6583 | 66 * MATLAB compatibility:: |
| 2866 | 67 * Index:: |
| 68 @end menu | |
| 69 | |
| 4830 | 70 @node What is Octave? |
| 2866 | 71 @chapter What is Octave? |
| 72 | |
| 73 Octave is a high-level interactive language, primarily intended for | |
| 74 numerical computations that is mostly compatible with | |
| 75 @sc{Matlab}.@footnote{@sc{Matlab} is a registered trademark of The MathWorks, | |
| 6583 | 76 Inc.} |
| 2866 | 77 |
| 6583 | 78 Octave can do arithmetic for real, complex or integer-valued scalars |
| 79 and matrices, solve sets of nonlinear algebraic equations, integrate | |
| 80 functions over finite and infinite intervals, and integrate systems of | |
| 81 ordinary differential and differential-algebraic equations. | |
| 2866 | 82 |
| 83 Octave uses the GNU readline library to handle reading and editing | |
| 84 input. By default, the line editing commands are similar to the | |
| 85 cursor movement commands used by GNU Emacs, and a vi-style line | |
| 86 editing interface is also available. At the end of each session, the | |
| 87 command history is saved, so that commands entered during previous | |
| 88 sessions are not lost. | |
| 89 | |
| 6879 | 90 The Octave distribution includes a 590+ page Texinfo manual. Access |
| 2866 | 91 to the complete text of the manual is available via the help command |
| 6583 | 92 @c really, the *complete* text? |
| 2866 | 93 at the Octave prompt. |
| 94 | |
| 6583 | 95 @menu |
| 96 * Who develops Octave?:: | |
| 6584 | 97 * Why GNU Octave?:: |
| 6583 | 98 * What version should I use?:: |
| 99 * On what platforms does Octave run?:: | |
| 100 @end menu | |
| 101 | |
| 102 @node Who develops Octave? | |
| 103 @section Who develops Octave? | |
| 104 | |
| 6584 | 105 Discussions about writing the software that would eventually become |
| 106 Octave started in about 1988 with James B. Rawlings and John W. Eaton at | |
| 107 the University of Texas. John W. Eaton was the original author of | |
| 108 Octave, starting full-time development in February 1992. He is still | |
| 109 the primary maintainer. The community | |
| 110 of users/developers has in addition contributed some code and fuels the | |
| 111 discussion on the mailing lists @email{help@@octave.org} (user forum), | |
| 112 @email{bug@@octave.org} (bug reports), @email{maintainers@@octave.org} | |
| 113 (development issues), and @email{octave-dev@@lists.sourceforge.net} (all | |
| 114 things related to the Octave Forge repository of user-contributed | |
| 115 functions). | |
| 6583 | 116 |
| 6584 | 117 @node Why GNU Octave? |
| 118 @section Why GNU Octave? | |
| 6583 | 119 |
| 6584 | 120 The GNU Project was launched in 1984 to develop a complete Unix-like |
| 121 operating system which is free software: the GNU system. | |
| 122 | |
| 123 GNU is a recursive acronym for ``GNU's Not Unix''; it is pronounced | |
| 124 guh-noo, approximately like canoe. | |
| 6583 | 125 |
| 6584 | 126 The Free Software Foundation (FSF) is the principal organizational |
| 127 sponsor of the GNU Project. | |
| 128 | |
| 129 Octave became GNU Octave in 1997 (beginning with version 2.0.6). This | |
| 130 meant agreeing to consider Octave a part of the GNU Project and support | |
| 131 the efforts of the FSF. However, Octave is not and has never been | |
| 132 developed by the FSF. | |
| 133 | |
| 134 For more information about the GNU project, see @url{www.gnu.org}. | |
| 6583 | 135 |
| 136 @cindex FSF [Free Software Foundation] | |
| 137 @cindex GNU [GNU's not unix] | |
| 138 | |
| 139 @node What version should I use? | |
| 140 @section What version should I use? | |
| 141 | |
| 142 In general, you will find the latest version on | |
| 6584 | 143 @url{http://www.octave.org/download.html}. It is |
| 6583 | 144 recommended to use the ``testing'' version of octave for general use, |
| 145 and the ``development'' version if you want the latest features. | |
| 146 | |
| 147 A list of user-visible changes since the last release is available in | |
| 148 the file @file{NEWS}. The file @file{ChangeLog} in the source | |
| 149 distribution contains a more detailed record of changes made since the | |
| 150 last release. | |
| 151 | |
| 152 @node On what platforms does Octave run? | |
| 153 @section On what platforms does Octave run? | |
| 154 | |
| 6584 | 155 Octave runs on various Unices---at least Linux and Solaris, Mac OS X, |
| 156 Windows and anything you can compile it on. Binary distributions exist | |
| 6583 | 157 at least for Debian, Suse, Fedora and RedHat Linuxes (Intel and AMD |
| 158 CPUs, at least), for Mac Os X and Windows' 98, 2000 and XP. | |
| 159 | |
| 2866 | 160 Two and three dimensional plotting is fully supported using gnuplot. |
| 161 | |
| 162 The underlying numerical solvers are currently standard Fortran ones | |
| 163 like Lapack, Linpack, Odepack, the Blas, etc., packaged in a library | |
| 164 of C++ classes. If possible, the Fortran subroutines are compiled | |
| 165 with the system's Fortran compiler, and called directly from the C++ | |
| 166 functions. If that's not possible, you can still compile Octave if | |
| 167 you have the free Fortran to C translator f2c. | |
| 168 | |
| 169 Octave is also free software; you can redistribute it and/or modify it | |
| 170 under the terms of the GNU General Public License as published by the | |
| 171 Free Software Foundation. | |
| 172 | |
| 4830 | 173 @node How can I cite Octave? |
| 174 @chapter How can I cite Octave? | |
| 4831 | 175 |
| 176 Pointing to @url{http://www.octave.org} is good, because that gives | |
| 177 people a direct way to find out more. If citation of a URL is not | |
| 178 allowed by a publisher, or if you also want to point to a traditional | |
| 179 reference, then you can cite the Octave manual: | |
| 4830 | 180 |
| 181 @example | |
| 182 @group | |
| 6584 | 183 @@BOOK@{eaton:2002, |
| 184 author = "John W. Eaton", | |
| 185 title = "GNU Octave Manual", | |
| 186 publisher = "Network Theory Limited", | |
| 187 year = "2002", | |
| 188 isbn = "0-9541617-2-6" | |
| 189 @} | |
| 4830 | 190 @end group |
| 191 @end example | |
| 192 | |
| 8128 | 193 @node Series 3.0.N |
| 194 @chapter What's new in version series 3.0.N and 3.1.N of Octave | |
| 6583 | 195 |
| 8128 | 196 The 3.0.N series has enough new features to justify a major version |
| 197 number change. The 3.0.N series brings | |
| 6583 | 198 |
| 199 @itemize @bullet | |
| 200 | |
| 201 @item integer types | |
| 202 | |
| 203 @item fixed point arithmetic | |
| 204 | |
| 205 @item sparse matrices | |
| 206 | |
| 207 @item Linear programming code based on GLPK | |
| 208 | |
| 209 @item 64-bit compilation support | |
| 210 | |
| 211 @item gzipped files and stream and consequently support of matlab v7 files | |
| 2866 | 212 |
| 6583 | 213 @item better support for both msvc and mingw |
| 214 | |
| 7116 | 215 @item a fully compatible MEX interface |
| 6583 | 216 |
| 6606 | 217 @item many many other minor features and compatibility changes |
| 6583 | 218 |
| 219 @end itemize | |
| 220 | |
| 6735 | 221 Here are some features that have been around since 2.1.N |
| 6583 | 222 |
| 223 @itemize @bullet | |
| 2866 | 224 |
| 6583 | 225 @item NDarrays |
| 226 | |
| 227 @item cells | |
| 228 | |
| 229 @end itemize | |
| 230 | |
| 8128 | 231 The 3.1.N series is the current development release and will become a |
| 232 3.2.N release in the future. This series brings the new features | |
| 233 | |
| 234 @itemize | |
| 235 @item OpenGL backend | |
| 236 | |
| 237 An experimental OpenGL graphics backend to replace the gnuplot | |
| 238 | |
| 239 @item Object Orient Programming | |
| 240 | |
| 241 @item Block comments | |
| 242 | |
| 243 @item imwrite and imread | |
| 244 | |
| 245 The functions are based on the GraphicsMagick library. | |
| 246 | |
| 247 @item Lazy transpose | |
| 248 | |
| 249 Special treatment in the parser of things like "a' * b", where the | |
| 250 transpose is never explicitly formed but a flag is rather passed to the | |
| 251 underlying LAPACK code. | |
| 252 | |
| 253 @item Single precision type | |
| 254 @end itemize | |
| 255 | |
| 256 | |
| 4830 | 257 @node Octave Features |
| 2866 | 258 @chapter What features are unique to Octave? |
| 259 | |
| 260 @menu | |
| 6583 | 261 * Functions defined on the command-line:: |
| 262 * Comments with #:: | |
| 263 * Strings delimitted by double quotes ":: | |
| 264 * Line continuation by backslash:: | |
| 265 * Informative block closing:: | |
| 266 * Coherent syntax:: | |
| 267 * Exclamation mark as not operator:: | |
| 2866 | 268 * Increment and decrement operators:: |
| 269 * Unwind-protect:: | |
| 6583 | 270 * Built-in ODE and DAE solvers:: |
| 2866 | 271 @end menu |
| 272 | |
| 8128 | 273 This section refers to Matlab R2008b and Octave 2.1.51. |
| 2866 | 274 |
| 6583 | 275 @node Functions defined on the command-line |
| 276 @section Functions defined on the command-line | |
| 2866 | 277 |
| 6583 | 278 Functions can be defined by entering code on the command line, a |
| 6584 | 279 feature not supported by the other leading brand. For example, you may |
| 6583 | 280 type: |
| 2866 | 281 |
| 282 @example | |
| 283 @group | |
| 6583 | 284 octave:1> function s = hello_string (to_who) |
| 285 > ## Say hello | |
| 286 > if nargin<1, to_who = "World"; end | |
| 287 > s = ["Hello ",\ | |
| 288 > to_who]; | |
| 289 > endfunction | |
| 290 octave:2> hello_string ("Moon") | |
| 291 ans = Hello Moon | |
| 2866 | 292 @end group |
| 293 @end example | |
| 294 | |
| 6583 | 295 @node Comments with # |
| 296 @section Comments with # | |
| 297 | |
| 6584 | 298 The pound character, @samp{#}, may be used to start comments, in addition |
| 299 to @samp{%}. See the previous example. The major advantage of this is | |
| 300 that as @samp{#} is also a comment character for unix script files, any | |
| 301 file that starts with a string like @samp{#! /usr/bin/octave -q} will be | |
| 302 treated as an octave script and be executed by octave. | |
| 2866 | 303 |
| 6583 | 304 @node Strings delimitted by double quotes " |
| 305 @section Strings delimitted by double quotes " | |
| 6584 | 306 The double quote, @samp{"}, may be used to delimit strings, in addition to |
| 307 the single quote @samp{'}. See the previous example. Also, double-quoted | |
| 308 strings include backslash interpretation (like C++, C, and Perl) while | |
| 309 single quoted are uninterpreted (like Matlab and Perl). | |
| 6583 | 310 |
| 311 @node Line continuation by backslash | |
| 312 @section Line continuation by backslash | |
| 313 | |
| 6584 | 314 Lines can be continued with a backslash, @samp{\}, in addition to three |
| 315 points @samp{@dots{}}. See the previous example. | |
| 6583 | 316 |
| 317 @node Informative block closing | |
| 318 @section Informative block closing | |
| 319 | |
| 6584 | 320 You may close @code{function}, @code{for}, @code{while}, @code{if}, |
| 321 @dots{} blocks with @code{endfunction}, @code{endfor}, @code{endwhile}, | |
| 322 @dots{} keywords in addition to using @code{end}. As with Matlab, the | |
| 323 @code{end} (or @code{endfunction}) keyword that marks the end of a | |
| 324 function defined in a @file{.m} file is optional. | |
| 2866 | 325 |
| 6583 | 326 @node Coherent syntax |
| 327 @section Coherent syntax | |
| 328 | |
| 329 Indexing other things than variables is possible, as in: | |
| 330 @example | |
| 331 @group | |
| 332 octave:1> [3 1 4 1 5 9](3) | |
| 333 ans = 4 | |
| 334 octave:2> cos([0 pi pi/4 7])(3) | |
| 335 ans = 0.70711 | |
| 336 @end group | |
| 337 @end example | |
| 338 | |
| 339 @node Exclamation mark as not operator | |
| 340 @section Exclamation mark as not operator | |
| 341 | |
| 342 The exclamation mark '!' (aka ``Bang!'') is a negation operator, just | |
| 343 like the tilde '~': | |
| 2866 | 344 |
| 345 @example | |
| 346 @group | |
| 6583 | 347 octave:1> if ! strcmp (program_name, "octave"), |
| 348 > "It's an error" | |
| 349 > else | |
| 350 > "It works!" | |
| 351 > end | |
| 352 ans = It works! | |
| 2866 | 353 @end group |
| 354 @end example | |
| 355 | |
| 4830 | 356 @node Increment and decrement operators |
| 2866 | 357 @section Increment and decrement operators |
| 358 | |
| 359 @cindex Increment operators | |
| 360 @cindex Decrement operators | |
| 361 @cindex Operators, increment | |
| 362 @cindex Operators, decrement | |
| 363 | |
| 6584 | 364 If you like the @samp{++}, @samp{+=} etc operators, rejoice! |
| 2866 | 365 Octave includes the C-like increment and decrement operators @samp{++} |
| 6583 | 366 and @samp{--} in both their prefix and postfix forms, in addition to |
| 367 @samp{+=}, @samp{-=}, @samp{*=}, @samp{/=}, @samp{^=}, @samp{.*=}, | |
| 368 @samp{./=}, and @samp{.^=}. | |
| 2866 | 369 |
| 370 For example, to pre-increment the variable @var{x}, you would write | |
| 371 @code{++@var{x}}. This would add one to @var{x} and then return the new | |
| 372 value of @var{x} as the result of the expression. It is exactly the | |
| 373 same as the expression @code{@var{x} = @var{x} + 1}. | |
| 374 | |
| 6584 | 375 To post-increment a variable @var{x}, you would write @code{x++}. |
| 2866 | 376 This adds one to the variable @var{x}, but returns the value that |
| 377 @var{x} had prior to incrementing it. For example, if @var{x} is equal | |
| 6584 | 378 to 2, the result of the expression @code{x++} is 2, and the new |
| 2866 | 379 value of @var{x} is 3. |
| 380 | |
| 381 For matrix and vector arguments, the increment and decrement operators | |
| 382 work on each element of the operand. | |
| 383 | |
| 384 | |
| 4830 | 385 @node Unwind-protect |
| 2866 | 386 @section Unwind-protect |
| 387 | |
| 388 @cindex Unwind-protect | |
| 389 | |
| 390 Octave supports a limited form of exception handling modelled after the | |
| 391 unwind-protect form of Lisp. The general form of an | |
| 392 @code{unwind_protect} block looks like this: | |
| 393 | |
| 394 @example | |
| 395 @group | |
| 396 unwind_protect | |
| 397 @var{body} | |
| 398 unwind_protect_cleanup | |
| 399 @var{cleanup} | |
| 400 end_unwind_protect | |
| 401 @end group | |
| 402 @end example | |
| 403 | |
| 404 @noindent | |
| 405 Where @var{body} and @var{cleanup} are both optional and may contain any | |
| 406 Octave expressions or commands. The statements in @var{cleanup} are | |
| 407 guaranteed to be executed regardless of how control exits @var{body}. | |
| 408 | |
| 409 The @code{unwind_protect} statement is often used to reliably restore | |
| 410 the values of global variables that need to be temporarily changed. | |
| 411 | |
| 8128 | 412 Matlab can be made to do something similar with their @code{OnCleanUp} |
| 413 function that was introduced in 2008a. | |
| 414 | |
| 4830 | 415 @node Built-in ODE and DAE solvers |
| 2866 | 416 @section Built-in ODE and DAE solvers |
| 417 | |
| 418 @cindex DASSL | |
| 419 @cindex LSODE | |
| 420 | |
| 421 Octave includes LSODE and DASSL for solving systems of stiff ordinary | |
| 422 differential and differential-algebraic equations. These functions are | |
| 423 built in to the interpreter. | |
| 424 | |
| 6583 | 425 @node Learning more about Octave |
| 426 @chapter What documentation exists for Octave? | |
| 427 | |
| 428 @menu | |
| 429 * Documentation:: | |
| 430 * Getting additional help:: | |
| 431 * User community:: | |
| 432 * Bug reports:: | |
| 433 @end menu | |
| 434 | |
| 435 | |
| 4830 | 436 @node Documentation |
| 6583 | 437 @section What documentation exists for Octave? |
| 2866 | 438 |
| 439 @cindex Octave, documentation | |
| 440 | |
| 6879 | 441 The Octave distribution includes a 590+ page manual that is also |
| 2866 | 442 distributed under the terms of the GNU GPL. |
| 6583 | 443 It is available on the web at |
| 444 @url{http://www.octave.org/docs.html} and you will also | |
| 445 find there instructions on how to order a paper version. | |
| 446 | |
| 447 The complete text of the Octave manual is also available using the GNU | |
| 448 Info system via the GNU Emacs, info, or xinfo programs, or by using | |
| 449 the @samp{help -i} command to start the GNU info browser directly from | |
| 450 the Octave prompt. | |
| 451 | |
| 452 If you have problems using this documentation, or find that some topic | |
| 453 is not adequately explained, indexed, or cross-referenced, please send | |
| 6584 | 454 a bug report to @email{bug@@octave.org}. |
| 6583 | 455 |
| 2866 | 456 |
| 6583 | 457 @node Getting additional help |
| 458 @section Getting additional help | |
| 459 | |
| 460 @cindex Additional help | |
| 461 @cindex Mailing lists, help-octave | |
| 462 | |
| 6584 | 463 If you can't find an answer to your question, the |
| 464 @email{help@@octave.org} mailing list is available for questions related | |
| 465 to using, installing, and porting Octave that are not adequately | |
| 466 answered by the Octave manual or by this document. | |
| 6583 | 467 |
| 468 @node User community | |
| 469 @section User community | |
| 470 | |
| 6584 | 471 To subscribe to the list, go to @url{www.octave.org/archive.html} and |
| 472 follow the link to the subscription page for the list. | |
| 2866 | 473 |
| 6653 | 474 @strong{Please do not} send requests to be added or removed from the |
| 6583 | 475 mailing list, or other administrative trivia to the list itself. |
| 476 | |
| 477 An archive of old postings to the help-octave mailing list is maintained | |
| 478 on @url{http://www.octave.org/archive.html}. | |
| 479 | |
| 6584 | 480 You will also find some user advice and code spread over the web. Good |
| 6583 | 481 starting points are the Octave Wiki @url{http://wiki.octave.org} and |
|
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482 Octave-Forge @url{http://octave.sourceforge.net} |
| 6583 | 483 |
| 484 @node Bug reports | |
| 485 @section I think I have found a bug in Octave. | |
| 486 | |
| 487 @cindex Bug in Octave, newly found | |
| 488 | |
| 489 ``I think I have found a bug in Octave, but I'm not sure. How do I know, | |
| 490 and who should I tell?'' | |
| 2866 | 491 |
| 6583 | 492 @cindex Manual, for Octave |
| 493 | |
| 494 First, see the section on bugs and bug reports in the Octave manual. | |
| 495 When you report a bug, make sure to describe the type of computer you | |
| 496 are using, the version of the operating system it is running, and the | |
| 497 version of Octave that you are using. Also provide enough code so that | |
| 498 the Octave maintainers can duplicate your bug. | |
| 499 | |
| 500 If you have Octave working at all, the easiest way to do this is to use | |
| 501 the Octave function @code{bug_report}. When you execute this function, | |
| 502 Octave will prompt you for a subject and then invoke the editor on a | |
| 503 file that already contains all the configuration information. When you | |
| 504 exit the editor, Octave will mail the bug report for you (in a unix-like | |
| 505 operating system). | |
| 506 | |
| 507 @cindex Octave bug report | |
| 508 @cindex Mailing lists, bug-octave | |
| 509 | |
| 510 If for some reason you cannot use Octave's @code{bug_report} function, | |
| 6584 | 511 mail your bug report to @email{bug@@octave.org}. Your message needs to |
| 6583 | 512 include enough information to allow the maintainers of Octave to fix the |
| 513 bug. Please read the section on bugs and bug reports in the Octave | |
| 514 manual for a list of things that should be included in every bug report. | |
| 515 | |
| 2866 | 516 |
| 4830 | 517 @node Getting Octave |
| 6583 | 518 @chapter Getting Octave |
| 2866 | 519 |
| 520 @menu | |
| 6583 | 521 * Source code:: |
| 522 * Pre-compiled binary packages:: | |
| 523 * Octave for other platforms:: | |
| 2866 | 524 @end menu |
| 525 | |
| 6583 | 526 @node Source code |
| 527 @section Source code | |
| 528 @cindex Source code | |
| 2866 | 529 |
| 6583 | 530 Source code is available on the Octave development site, where you are |
| 531 sure to get the latest version. | |
| 2866 | 532 |
| 6583 | 533 @itemize @bullet |
| 534 @item @url{http://www.octave.org/download.html} | |
| 535 @item @url{ftp://ftp.octave.org/pub/octave/} | |
| 536 @end itemize | |
| 2866 | 537 |
| 6583 | 538 Since Octave is distrubted under the terms of the GPL, you can get |
| 539 Octave from a friend who has a copy, by anonymous FTP, or by ordering | |
| 540 a tape or CD-ROM from the Free Software Foundation (FSF). | |
| 2866 | 541 |
| 6583 | 542 @node Pre-compiled binary packages |
| 543 @section Pre-compiled binary packages | |
| 544 @cindex Pre-compiled binary packages | |
| 545 @cindex Binaries | |
| 2866 | 546 |
| 6584 | 547 The Octave project does not distribute binary packages, but other |
| 548 projects do. For an up-to-date listing of packagers, see: | |
| 2866 | 549 |
| 6583 | 550 @itemize @bullet |
| 551 @item @url{http://www.octave.org/download.html} | |
| 552 @item @url{http://wiki.octave.org/wiki.pl?CategoryInstall} | |
| 553 @end itemize | |
| 2866 | 554 |
| 6583 | 555 As of today, Octave binaries are available at least on Debian, RedHat, |
| 556 Suse and Fedora Linuxes, Mac OS X, Windows' 98, 2000 and XP. | |
| 2866 | 557 |
| 4830 | 558 @node Octave for other platforms |
| 2866 | 559 @section How do I get a copy of Octave for (some other platform)? |
| 560 | |
| 561 @cindex VMS support | |
| 562 @cindex VAX | |
| 563 @cindex MS-DOS support | |
| 3154 | 564 @cindex Windows support |
| 2866 | 565 @cindex DJGPP |
| 566 @cindex EMX | |
| 567 @cindex OS/2 support | |
| 568 | |
| 6879 | 569 Octave currently runs on Unix-like systems, Mac OS X, and Windows. |
| 570 It should be possible to make Octave work on other systems as well. | |
| 571 If you are interested in porting Octave to other systems, please contact | |
| 6584 | 572 @email{bug@@octave.org}. |
| 2866 | 573 |
| 6583 | 574 @c @menu |
| 575 @c * Octave for Unix:: | |
| 576 @c * Octave for other platforms:: | |
| 577 @c * latest versions:: | |
| 578 @c @end menu | |
| 2866 | 579 |
| 6583 | 580 @c @cindex Octave, ordering |
| 581 @c @cindex Octave, getting a copy | |
| 2866 | 582 |
| 4830 | 583 @node Installation |
| 2866 | 584 @chapter Installation Issues and Problems |
| 585 | |
| 586 @cindex Octave, building | |
| 587 | |
| 8128 | 588 Octave 3.2 require approximately 800MB of disk storage to unpack |
| 6584 | 589 and compile from source (considerably less if you don't compile with |
| 590 debugging symbols). Once installed, Octave requires approximately 200MB | |
| 591 of disk space (again, considerably less if you don't compile with | |
| 592 debugging symbols). | |
| 2866 | 593 |
| 594 @menu | |
| 595 * What else do I need?:: | |
| 596 * Other C++ compilers?:: | |
| 597 @end menu | |
| 598 | |
| 4830 | 599 @node What else do I need? |
| 2866 | 600 @section What else do I need? |
| 601 | |
| 602 @cindex GNU gcc | |
| 603 @cindex GNU g++ | |
| 604 @cindex libg++ | |
| 605 @cindex GNU Make | |
| 606 @cindex Flex | |
| 607 @cindex GNU Bison | |
| 608 | |
| 3154 | 609 To compile Octave, you will need a recent version of GNU Make. You |
| 6584 | 610 will also need GCC 3.3 or later, although GCC 4.1 or later is |
| 611 recommended. | |
| 3154 | 612 |
| 6584 | 613 @strong{You must have GNU Make to compile octave}. Octave's Makefiles |
| 3154 | 614 use features of GNU Make that are not present in other versions of make. |
| 615 GNU Make is very portable and easy to install. | |
| 2866 | 616 |
| 4830 | 617 @node Other C++ compilers? |
| 2866 | 618 @section Can I compile Octave with another C++ compiler? |
| 619 | |
| 6584 | 620 Yes, but development is done primarily with GCC, so you may hit some |
| 621 incompatibilities. Octave is intended to be portable to any standard | |
| 622 conforming compiler. If you have difficulties that you think are bugs, | |
| 623 please report them to the @email{bug@@octave.org} mailing list, or ask | |
| 624 for help on the @email{help@@octave.org} mailing list. | |
| 2866 | 625 |
| 4830 | 626 @node Common problems |
| 2866 | 627 @chapter Common problems |
| 628 | |
| 629 This list is probably far too short. Feel free to suggest additional | |
| 630 questions (preferably with answers!) | |
| 631 | |
| 632 @itemize @bullet | |
| 633 @item | |
| 634 Octave takes a long time to find symbols. | |
| 635 | |
| 6606 | 636 Octave uses the @code{genpath} function to recursively add directories |
| 6900 | 637 to the list of directories searched for function files. Check the list |
| 6606 | 638 of directories with the @code{path} command. If the path list is very |
| 639 long check your use of the @code{genpath} function. | |
| 6735 | 640 |
| 641 @item | |
| 6900 | 642 When plotting Octave occasionally gives me errors like @samp{gnuplot> 9 0.735604 |
| 643 line 26317: invalid command}. | |
| 6735 | 644 |
| 645 There is a known bug in gnuplot 4.2 that can cause an off by one error | |
| 646 while piping data to gnuplot. The relevant gnuplot bug report can be | |
| 647 found at @url{http://sourceforge.net/tracker/index.php?func=detail&aid=1716556&group_id=2055&atid=102055} | |
| 648 | |
| 649 If you have obtained your copy of Octave from a distribution please file | |
| 650 a bug report requesting that the fix reported in the above bug report be | |
| 651 included. | |
|
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652 |
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653 @item |
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654 I cannot install a package. Octave complains about a missing @code{mkoctfile}. |
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655 |
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656 Most distributions split Octave into several packages. The script |
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657 @code{mkoctfile} is then part of a separate package: |
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658 @itemize @minus |
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659 @item |
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660 Debian/Ubuntu |
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661 |
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662 @code{aptitude install octave3.0-headers} |
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663 |
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664 @item |
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665 Fedora |
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666 |
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667 @code{yum install octave-devel} |
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668 |
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669 @end itemize |
| 2866 | 670 @end itemize |
| 671 | |
| 6584 | 672 @node How do I ...? |
| 673 @chapter How do I ...? | |
| 2866 | 674 |
| 6583 | 675 @menu |
| 676 * How do I set the number of displayed decimals?:: | |
| 677 @end menu | |
| 2866 | 678 |
| 6583 | 679 @cindex Tips and tricks |
| 6584 | 680 @cindex How do I @dots{} ? |
| 2866 | 681 |
| 6583 | 682 @node How do I set the number of displayed decimals? |
| 683 @section How do I set the number of displayed decimals? | |
| 2866 | 684 |
| 685 @example | |
| 686 @group | |
| 6583 | 687 octave:1> format long |
| 688 octave:2> pi | |
| 689 pi = 3.14159265358979 | |
| 690 octave:3> format short | |
| 691 octave:4> pi | |
| 692 pi = 3.1416 | |
| 2866 | 693 @end group |
| 694 @end example | |
| 695 | |
| 4830 | 696 @node MATLAB compatibility |
| 2866 | 697 @chapter Porting programs from @sc{Matlab} to Octave |
| 698 | |
| 699 @cindex @sc{Matlab} compatibility | |
| 700 @cindex Compatibility with @sc{Matlab} | |
| 701 | |
| 6612 | 702 People often ask |
| 703 | |
| 2866 | 704 ``I wrote some code for @sc{Matlab}, and I want to get it running under |
| 705 Octave. Is there anything I should watch out for?'' | |
| 706 | |
| 6612 | 707 or alternatively |
| 708 | |
| 709 ``I wrote some code in Octave, and want to share it with @sc{Matlab} | |
| 6900 | 710 users. Is there anything I should watch out for?'' |
| 6612 | 711 |
| 6900 | 712 which is not quite the same thing. There are still a number of |
| 6612 | 713 differences between Octave and @sc{Matlab}, however in general |
| 714 differences between the two are considered as bugs. Octave might | |
| 715 consider that the bug is in @sc{Matlab} and do nothing about it, but | |
| 716 generally functionality is almost identical. If you find a difference | |
| 717 between Octave behavior and @sc{Matlab}, then you should send a | |
| 718 description of this difference (with code illustrating the difference, | |
| 719 if possible) to @email{bug@@octave.org}. | |
| 720 | |
| 721 Furthermore, Octave adds a few syntactical extensions to Matlab that | |
| 722 might cause some issues when exchanging files between Matlab and Octave | |
| 723 users. As both Octave and @sc{Matlab} are under constant development the | |
| 724 information in this section is subject to change at anytime. | |
| 725 | |
| 726 You should also look at the page | |
| 727 @url{http://octave.sourceforge.net/packages.html} and | |
| 728 @url{http://octave.sourceforge.net/doc/} that has a function reference | |
| 729 that is up to date. You can use this function reference to see the | |
| 730 number of octave function that are available and their @sc{Matlab} | |
| 731 compatibility. | |
| 732 | |
| 8128 | 733 The major differences between Octave 3.2.N and @sc{Matlab} R2008a are: |
| 6612 | 734 |
| 735 @itemize @bullet | |
| 736 @item Nested Functions | |
| 737 | |
| 6900 | 738 Octave doesn't yet have nested functions. That is |
| 2866 | 739 |
| 6612 | 740 @example |
| 741 @group | |
| 742 function y = foo (x) | |
| 6900 | 743 y = bar(x) |
| 744 function y = bar (x) | |
| 745 y = @dots{}; | |
| 746 end | |
| 6612 | 747 end |
| 748 @end group | |
| 749 @end example | |
| 750 | |
| 751 There was discussion in Octave of having these even prior to @sc{Matlab}, | |
| 752 and the decision was made not to have these in Octave at the time for | |
| 6900 | 753 compatibility. The above written with sub-functions functions would be |
| 6612 | 754 |
| 755 @example | |
| 756 @group | |
| 757 function y = foo (x) | |
| 758 y = bar(x) | |
| 759 end | |
| 760 function y = bar (x) | |
| 761 y = @dots{}; | |
| 762 end | |
| 763 @end group | |
| 764 @end example | |
| 765 | |
| 766 Now that @sc{Matlab} has recently introduced nested functions, Octave will | |
| 6900 | 767 probably have them soon as well. Until then nested functions in Octave |
| 6612 | 768 are treated as sub-functions with the same scoping rules as |
| 769 sub-functions. | |
| 770 | |
| 771 The authors of Octave consider the nested function scoping rules of | |
| 772 Matlab to be more problems than they are worth as they introduce | |
| 773 diffiult to find bugs as inadvertantly modifying a variable in a | |
| 774 nested function that is also used in the parent is particularly easy. | |
| 775 | |
| 776 @item Differences in core syntax | |
| 777 There a few core @sc{Matlab} syntaxes that are not accepted by Octave, | |
| 778 these being | |
| 779 | |
| 780 @itemize @bullet | |
| 2866 | 781 @item |
| 6612 | 782 Some limitations on the use of function handles. The major difference is |
| 6879 | 783 related to nested function scoping rules (as above) and their use with |
| 6612 | 784 function handles. |
| 2866 | 785 |
| 786 @item | |
| 6612 | 787 Some limitations of variable argument lists on the LHS of an expression, |
| 788 though the most common types are accepted. | |
| 789 | |
| 2866 | 790 @item |
| 8128 | 791 @sc{Matlab} classdef object oriented programming is not yet supportted, |
| 792 though work is underway and when development more on to Octave 3.3 this | |
| 793 will be included in teh development tree. | |
| 6612 | 794 @end itemize |
| 795 | |
| 796 @item Differences in core functions | |
| 797 A large number of the @sc{Matlab} core functions (ie those that are in | |
| 798 the core and not a toolbox) are implemented, and certainly all of the | |
| 799 commonly used ones. There are a few functions that aren't implemented, | |
| 6879 | 800 for example @code{condest} or to do with specific missing Octave functionality |
| 6612 | 801 (gui, dll, java, activex, dde, web, and serial functions). Some of the |
| 802 core functions have limitations that aren't in the @sc{Matlab} | |
| 6900 | 803 version. For example the @code{sprandn} function can not force a |
| 6735 | 804 particular condition number for the matrix like @sc{Matlab} can. |
| 6612 | 805 |
| 806 @item Just-In-Time compiler | |
| 807 @sc{Matlab} includes a "Just-In-Time" compiler. This compiler allows the | |
| 808 acceleration of for-loops in @sc{Matlab} to almost native performance with | |
| 809 certain restrictions. The JIT must know the return type of all functions | |
| 810 called in the loops and so you can't include user functions in the loop | |
| 6900 | 811 of JIT optimized loops. Octave doesn't have a JIT and so to some might |
| 812 seem slower than @sc{Matlab}. For this reason you must vectorize your code as | |
| 813 much as possible. The MathWorks themselves have a good document | |
| 814 discussing vectorization at | |
| 6612 | 815 @url{http://www.mathworks.com/support/tech-notes/1100/1109.html}. |
| 816 | |
| 817 @item Compiler | |
| 818 On a related point, there is no Octave compiler, and so you can't | |
| 819 convert your Octave code into a binary for additional speed or | |
| 6900 | 820 distribution. There is an example of how to do this at |
| 6612 | 821 @url{http://www.stud.tu-ilmenau.de/~rueckn/}, but this is a very early |
| 822 example code and would need lots of work to complete it. | |
| 823 | |
| 824 @item Graphic Handles | |
| 825 Up to Octave 2.9.9 there was no support for graphic handles in Octave | |
| 8128 | 826 itself. In the 3.2.N versions of Octave the support for graphics |
| 827 handles is converging towards full compatibility. The @code{patch} | |
| 828 function is currently limited to 2-D patches, due to an underlying | |
| 829 limitation in gnuplot. | |
| 6612 | 830 |
| 831 @item GUI | |
| 6900 | 832 There are no @sc{Matlab} compatible GUI functions. There are a number of |
| 833 bindings from Octave to Tcl/Tk, Vtk and zenity included in the | |
| 834 Octave Forge project (@url{http://octave.sourceforge.net}) for example | |
| 6612 | 835 that can be used for a GUI, but these are not @sc{Matlab} |
| 7116 | 836 compatible. Work on a matlab compatible GUI is in an alpha stage in the |
| 6879 | 837 JHandles package (@url{http://octave.sourceforge.net/jhandles/index.html}). |
| 838 This might be an issue if you intend to exchange Octave code with | |
| 839 @sc{Matlab} users. | |
| 6612 | 840 |
| 841 @item Simulink | |
| 842 Octave itself includes no Simulink support. Typically the simulink | |
| 843 models lag research and are less flexible, so shouldn't really be used | |
| 6900 | 844 in a research environment. However, some @sc{Matlab} users that try to |
| 845 use Octave complain about this lack. There is a similar package to | |
| 846 simulink for the Octave and R projects available at | |
| 847 @url{http://www.scicraft.org/} | |
| 6612 | 848 |
| 849 @item Mex-Files | |
| 850 Octave includes an API to the matlab MEX interface. However, as MEX is | |
| 6900 | 851 an API to the internals of @sc{Matlab} and the internals of Octave |
| 852 differ from @sc{Matlab}, there is necessarily a manipulation of the data | |
| 853 to convert from a MEX interface to the Octave equivalent. This is | |
| 854 notable for all complex matrices, where @sc{Matlab} stores complex | |
| 855 arrays as real and imaginary parts, whereas Octave respects the C99/C++ | |
| 856 standards of co-locating the real/imag parts in memory. Also due to the | |
| 857 way @sc{Matlab} allows access to the arrays passed through a pointer, | |
| 858 the MEX interface might require copies of arrays (even non complex | |
| 8128 | 859 ones). |
| 6612 | 860 |
| 861 @item Block comments | |
| 8128 | 862 Block comments denoted by "%@{" and "%@}" markers are supported by |
| 863 Octave with some limitations. The major limitation is that block | |
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864 comments are not supported with [] or @{@}. |
| 6612 | 865 |
| 866 @item Mat-File format | |
| 867 There are some differences in the mat v5 file format accepted by | |
| 868 Octave. @sc{Matlab} recently introduced the "-V7.3" save option which is | |
| 6900 | 869 an HDF5 format which is particularly useful for 64-bit platforms where |
| 6612 | 870 the standard matlab format can not correctly save variables.. Octave |
| 6900 | 871 accepts HDF5 files, but is not yet compatible with the "-v7.3" versions |
| 6612 | 872 produced by @sc{Matlab}. |
| 873 | |
| 8128 | 874 Although Octave can load inline abd function handles saved by |
| 875 @sc{Matlab}, it can not yet save them. | |
| 6612 | 876 |
| 877 Finally, Some multi-byte unicode characters aren't yet treated in | |
| 878 mat-files. | |
| 879 | |
| 880 @item Profiler | |
| 881 Octave doesn't have a profiler. Though there is a patch for a flat | |
| 882 profiler, that might become a real profiler sometime in the future. see | |
| 883 the thread | |
| 884 | |
| 885 @url{http://www.cae.wisc.edu/pipermail/octave-maintainers/2007-January/001685.html} | |
| 886 | |
| 887 for more details | |
| 888 | |
| 889 @item Toolboxes | |
| 890 Octave is a community project and so the toolboxes that exist are | |
| 6900 | 891 donated by those interested in them through the Octave Forge website |
| 6612 | 892 (@url{http://octave.sourceforge.net}). These might be lacking in certain |
| 893 functionality relative to the @sc{Matlab} toolboxes, and might not | |
| 894 exactly duplicate the matlab functionality or interface. | |
| 895 | |
| 896 @item Short-circuit & and | operators | |
| 6900 | 897 The @code{&} and @code{|} operators in @sc{Matlab} short-circuit when |
| 898 included in an if statemant and not otherwise. In Octave only the | |
| 899 @code{&&} and @code{||} short circuit. Note that this means that | |
| 6612 | 900 |
| 901 @example | |
| 902 @group | |
| 903 if (a | b) | |
| 904 @dots{} | |
| 905 end | |
| 906 @end group | |
| 907 @end example | |
| 908 | |
| 909 and | |
| 910 | |
| 911 @example | |
| 912 @group | |
| 913 t = a | b; | |
| 914 if t | |
| 915 @dots{} | |
| 916 end | |
| 917 @end group | |
| 918 @end example | |
| 919 | |
| 6900 | 920 @noindent |
| 6612 | 921 are different in @sc{Matlab}. This is really a @sc{Matlab} bug, but |
| 922 there is too much code out there that relies on this behavior to change | |
| 923 it. Prefer the || and && operators in if statements if possible. | |
| 2866 | 924 |
| 6612 | 925 Note that the difference is also significant when either argument is a |
| 926 function with side effects or if the first argument is a scalar and the | |
| 927 second argument is an empty matrix. For example, note the difference | |
| 928 between | |
| 929 | |
| 930 @example | |
| 931 @group | |
| 932 t = 1 | []; ## results in [], so... | |
| 933 if (t) 1, end ## in if ([]), this is false. | |
| 934 @end group | |
| 935 @end example | |
| 936 | |
| 937 and | |
| 938 | |
| 939 @example | |
| 940 if (1 | []) 1, end ## short circuits so condition is true. | |
| 941 @end example | |
| 942 | |
| 943 Another case that is documented in the @sc{Matlab} manuals is that | |
| 944 | |
| 945 @example | |
| 946 @group | |
| 947 t = [1, 1] | [1, 2, 3]; ## error | |
| 948 if ([1, 1] | [1, 2, 3]) 1, end ## OK | |
| 949 @end group | |
| 950 @end example | |
| 951 | |
| 952 Also @sc{Matlab} requires the operands of && and || to be scalar values but | |
| 953 Octave does not (it just applies the rule that for an operand to be | |
| 954 considered true, every element of the object must be nonzero or | |
| 955 logically true). | |
| 956 | |
| 957 Finally, note the inconsistence of thinking of the condition of an if | |
| 958 statement as being equivalent to @code{all(X(:))} when @var{X} is a | |
| 959 matrix. This is true for all cases EXCEPT empty matrices: | |
| 960 | |
| 961 @example | |
| 962 @group | |
| 963 if ([0, 1]) == if (all ([0, 1])) ==> i.e., condition is false. | |
| 964 if ([1, 1]) == if (all ([1, 1])) ==> i.e., condition is true. | |
| 965 @end group | |
| 966 @end example | |
| 967 | |
| 968 However, | |
| 969 | |
| 970 @example | |
| 971 if ([]) != if (all ([])) | |
| 972 @end example | |
| 973 | |
| 6900 | 974 because @code{samp ([]) == 1} (because, despite the name, it is really |
| 6612 | 975 returning true if none of the elements of the matrix are zero, and since |
| 976 there are no elements, well, none of them are zero). But, somewhere | |
| 977 along the line, someone decided that if @code{([])} should be false. | |
| 978 Mathworks probably thought it just looks wrong to have @code{[]} be true | |
| 979 in this context even if you can use logical gymnastics to convince | |
| 980 yourself that "all" the elements of a matrix that doesn't actually have | |
| 981 any elements are nonzero. Octave however duplicates this behavior for if | |
| 982 statements containing empty matrices. | |
| 983 | |
| 984 @item Octave extensions | |
| 985 The extensions in Octave over @sc{Matlab} syntax are | |
| 986 very useful, but might cause issues when sharing with @sc{Matlab} users. | |
| 987 A list of the major extensions that should be avoided to be compatible | |
| 988 with @sc{Matlab} are | |
| 989 | |
| 990 @itemize @bullet | |
| 991 @item | |
| 6900 | 992 Comments in octave can be marked with @samp{#}. This allows POSIX |
| 993 systems to have the first line as @samp{#! octave -q} and mark the script | |
| 6653 | 994 itself executable. @sc{Matlab} doesn't have this feature due to the |
| 6900 | 995 absence of comments starting with @samp{#}". |
| 2866 | 996 |
| 6612 | 997 @item |
| 998 Code blocks like if, for, while, etc can be terminated with block | |
| 999 specific terminations like "endif". @sc{Matlab} doesn't have this and | |
| 1000 all blocks must be terminated with "end" | |
| 1001 | |
| 1002 @item | |
| 1003 Octave has a lisp like unwind_protect block that allows blocks of | |
| 1004 code that terminate in an error to ensure that the variables that | |
| 1005 are touched are restored. You can do something similar with | |
| 6900 | 1006 @code{try}/@code{catch} combined with @samp{rethrow (lasterror ())} in |
| 1007 @sc{Matlab}, however rethrow and lasterror are only available in Octave 2.9.10 and later. | |
| 6612 | 1008 |
| 6900 | 1009 Note that using @code{try}/@code{catch} combined with @samp{rethrow |
| 1010 (lasterror ())} can not guarentee that global variables will be | |
| 1011 correctly reset, as it won't catch user interrupts with Ctrl-C. For | |
| 1012 example | |
| 6612 | 1013 |
| 1014 @example | |
| 1015 @group | |
| 1016 global a | |
| 1017 a = 1; | |
| 1018 try | |
| 1019 _a = a; | |
| 1020 a = 2 | |
| 1021 while true | |
| 1022 end | |
| 1023 catch | |
| 1024 fprintf ('caught interrupt\n'); | |
| 1025 a = _a; | |
| 1026 rethrow (lasterror()); | |
| 1027 end | |
| 1028 @end group | |
| 1029 @end example | |
| 1030 | |
| 1031 @noindent | |
| 1032 compared to | |
| 1033 | |
| 1034 @example | |
| 1035 @group | |
| 1036 global a | |
| 1037 a = 1; | |
| 1038 unwind_protect | |
| 1039 _a = a; | |
| 1040 a = 2 | |
| 1041 while true | |
| 1042 end | |
| 1043 unwind_protect_cleanup | |
| 1044 fprintf ('caught interrupt\n'); | |
| 1045 a = _a; | |
| 1046 end | |
| 1047 @end group | |
| 1048 @end example | |
| 1049 | |
| 1050 Typing Ctrl-C in the first case returns the user directly to the | |
| 6879 | 1051 prompt, and the variable "a" is not reset to the saved value. In the |
| 6900 | 1052 second case the variable "a" is reset correctly. Therefore @sc{Matlab} |
| 6612 | 1053 gives no save way of temporarily changing global variables. |
| 1054 | |
| 1055 @item | |
| 1056 Indexing can be applied to all objects in Octave and not just | |
| 1057 variable. Therefore @code{sin(x)(1:10);} for example is perfectly valid | |
| 1058 in Octave but not @sc{Matlab}. To do the same in @sc{Matlab} you must do | |
| 1059 @code{y = sin(x); y = y([1:10]);} | |
| 1060 | |
| 1061 @item | |
| 6900 | 1062 Octave has the operators "++", "--", "-=", "+=", "*=", etc. As |
| 6612 | 1063 @sc{Matlab} doesn't, if you are sharing code these should be avoided. |
| 1064 | |
| 1065 @item | |
| 6900 | 1066 Character strings in Octave can be denoted with double or single |
| 1067 quotes. There is a subtle difference between the two in that escaped | |
| 1068 characters like @code{\n} (newline), @code{\t} (tab), etc are | |
| 1069 interpreted in double quoted strings but not single quoted strings. This | |
| 1070 difference is important on Windows platforms where the "\" character is | |
| 1071 used in path names, and so single quoted strings should be used in | |
| 1072 paths. @sc{Matlab} doesn't have double quoted strings and so they should | |
| 1073 be avoided if the code will be transfered to a @sc{Matlab} user. | |
| 6612 | 1074 @end itemize |
| 1075 | |
| 1076 @end itemize | |
| 2866 | 1077 |
| 4830 | 1078 @node Index |
| 2866 | 1079 @appendix Concept Index |
| 1080 | |
| 1081 @printindex cp | |
| 1082 | |
| 1083 @page | |
| 1084 @contents | |
| 1085 @bye |