Summary of changes since version 2.0.5: -------------------------------------- * New operators. Octave's parser now recognizes the following operators: << >> += -= *= /= .+= .-= .*= ./= &= |= <<= >>=. So far, there are only a few operations defined that actually use them (this should change before 2.1 is released). * New built-in data types: logical: A true value is represented by 1, and false value by 0. Comparison operations like <, <=, ==, >, >=, and != now return logical values. Indexing operations that use zero-one style indexing must now use logical values. You can use the new function logical() to convert a numeric value to a logical value. This avoids the need for the built-in variable `prefer_zero_one_indexing', so it has been removed. Logical values are automatically converted to numeric values where appropriate. file: A file object represents an open Octave stream object. The fopen function now returns a file object instead of an integer. File objects can be converted to integers automatically, and the other functions that work with file ids still work with integers, so this change should be backward compatible. The binary left-shift operator `<<' has been defined to work as in C++ for file objects and built-in types. For example, my_stream = fopen ("foo", "w"); my_stream << "x = " << pi << " marks the spot\n"; writes `x = 3.1416 marks the spot' in the file foo. The built-in variables stdin, stdout, and stderr are now also file objects instead of integers. list: A list is an array of Octave objects. It can be indexed using the normal indexing operator. For example, x = make_list ([1,2;3,4], 1, "foo"); stdout << x(2) << "\n" 1 stdout << x; ( [1] = 1 2 3 4 [2] = 1 [3] = foo ) There is currently no special syntax for creating lists; you must use the make_list function. * Commas in global statements are no longer special. They are now treated as command separators. This removes a conflict in the grammar and is consistent with the way Matlab behaves. The variable `warn_comma_in_global_decl' has been eliminated. * It is now possible to declare static variables that retain their values across function calls. For example, function ncall = f () static n = 0; ncall = ++n; endfunction defines a function that returns the number of times that it has been called. * Functions like quad, fsolve, and lsode can take either a function name or a simple function body as a string. For example, quad ("sqrt (x)", 0, 1) is equivalent to function y = f (x) y = sqrt (x); endfunction quad ("f", 0, 1) * If the argument to eig() is symmetric, Octave uses the specialized Lapack subroutine for symmetric matrices for a significant increase in performance. * If the argument to lsode that names the user-supplied function is a 2-element string array, the second element is taken as the name of the Jacobian function. The named function should have the following form: JAC = f (X, T) where JAC is the Jacobian matrix of partial derivatives of the right-hand-side functions that define the set of differential equations with respect to the state vector X. Summary of changes for version 2.0.5: ------------------------------------ * A `switch' statement is now available. See the Statements chapter in the manual for details. * Commands like ls, save, and cd may now also be used as formal parameters for functions. * More tests. Summary of changes for version 2.0.4: ------------------------------------ * It is now possible to use commands like ls, save, and cd as simple variable names. They still cannot be used as formal parameters for functions, or as the names of structure variables. Failed assignments leave them undefined (you can recover the orginal function definition using clear). * Is is now possible to invoke commands like ls, save, and cd as normal functions (for example, load ("foo", "x", "y", "z")). Summary of changes for version 2.0.3: ------------------------------------ * The manual has been completely revised and now corresponds much more closely to the features of the current version. * The return value for assignment expressions is now the RHS since that is more consistent with the way other programming languages work. However, Octave still prints the entire LHS value so that x = zeros (1, 2); x(2) = 1 still prints x = 0 1 but an assignment like z = x(2) = 1 sets z to 1 (not [ 0, 1 ] as in previous versions of Octave). * It is now much easier to make binary distributions. See the Binary Distributions section of the manual for more details. Summary of changes for version 2.0.2: ------------------------------------ * Octave now stops executing commands from a script file if an error is encountered. * The return, and break commands now cause Octave to quit executing commands from script files. When used in invalid contexts, the break, continue, and return commands are now simply ignored instead of producing parse errors. * size ("") is now [0, 0]. * New functions: sleep -- pause execution for a specified number of seconds usleep -- pause execution for a specified number of microseconds Summary of changes for version 2.0: ---------------------------------- * The set and show commands for setting and displaying gnuplot parameters have been replaced by gset and gshow. This change will probably break lots of things, but it is necessary to allow for compatibility with the Matlab graphics and GUI commands in a future version of Octave. (For now, the old set and show commands do work, but they print an annoying warning message to try to get people to switch to using gset.) * Octave has been mostly ported to Windows NT and Windows 95 using the beta 17 release of the Cygnus GNU-WIN32 tools. Not everything works, but it is usable. See the file README.WINDOWS for more information. * Dynamic linking works on more systems using dlopen() and friends (most modern Unix systems) or shl_load() and friends (HP/UX systems). A simple example is provided in examples/hello.cc. For this feature to work, you must configure Octave with --enable-shared. You may also need to have a shared-library version of libg++ and libstdc++. * New data types can be added to Octave by writing a C++ class. On systems that support dynamic linking, new data types can be added to an already running Octave binary. A simple example appears in the file examples/make_int.cc. Other examples are the standard Octave data types defined in the files src/ov*.{h,cc} and src/op-*.cc. * The configure option --enable-bounds-check turns on bounds checking on element references for Octave's internal array and matrix classes. It's enabled by default. To disable this feature, configure Octave with --disable-bounds-check. * The C-style I/O functions (fopen, fprintf, etc.) have been rewritten to be more compatible with Matlab. The fputs function has also been added. Usage of the *printf functions that was allowed in previous versions of Octave should still work. However, there is no way to make the new versions of the *scanf functions compatible with Matlab *and* previous versions of Octave. An optional argument to the *scanf functions is now available to make them behave in a way that is compatible with previous versions of Octave. * Octave can now read files that contain columns of numbers only, with no header information. The name of the loaded variable is constructed from the file name. Each line in the file must have the same number of elements. * The interface to the pager has changed. The new built-in variable `page_output_immediately' controls when Octave sends output to the pager. If it is nonzero, Octave sends output to the pager as soon as it is available. Otherwise, Octave buffers its output and waits until just before the prompt is printed to flush it to the pager. * Expressions of the form A(i,j) = x where X is a scalar and the indices i and j define a matrix of elements now work as you would expect rather than giving an error. I am told that this is how Matlab 5.0 will behave when it is released. * Indexing of character strings now works. * The echo command has been implemented. * The document command is now a regular function. * New method for handling errors: try BODY catch CLEANUP end_try_catch Where BODY and CLEANUP are both optional and may contain any Octave expressions or commands. The statements in CLEANUP are only executed if an error occurs in BODY. No warnings or error messages are printed while BODY is executing. If an error does occur during the execution of BODY, CLEANUP can access the text of the message that would have been printed in the builtin constant __error_text__. This is the same as eval (TRY, CATCH) (which may now also use __error_text__) but it is more efficient since the commands do not need to be parsed each time the TRY and CATCH statements are evaluated. * Octave no longer parses the help command by grabbing everything after the keyword `help' until a newline character is read. To get help for `;' or `,', now, you need to use the command `help semicolon' or `help comma'. * Octave's parser now does some simple constant folding. This means that expressions like 3*i are now evaluated only once, when a function is compiled, and the right hand side of expressions like a = [1,2;3,4] are treated as true matrix constants rather than lists of elements which must be evaluated each time they are needed. * Built-in variables that can take values of "true" and "false" can now also be set to any nonzero scalar value to indicate "true", and 0 to indicate "false". * New built-in variables `history_file', `history_size', and `saving_history'. * New built-in variable `string_fill_char' specifies the character to fill with when creating arrays of strings. * If the new built-in variable `gnuplot_has_frames' is nonzero, Octave assumes that your copy of gnuplot includes support for multiple plot windows when using X11. If the new built-in variable `gnuplot_has_multiplot' is nonzero, Octave assumes that your copy of gnuplot has the multiplot support that is included in recent 3.6beta releases. The initial values of these variables are determined by configure, but can be changed in your startup script or at the command line in case configure got it wrong, or if you upgrade your gnuplot installation. * The new plot function `figure' allows multiple plot windows when using newer versions of gnuplot with X11. * Octave now notices when the plotter has exited unexpectedly. * New built-in variable `warn_missing_semicolon'. If nonzero, Octave will warn when statements in function definitions don't end in semicolons. The default value is 0. * Octave now attempts to continue after floating point exceptions or out-of-memory errors. * If Octave crashes, it now attempts to save all user-defined variables in a file named `octave-core' in the current directory before exiting. * It is now possible to get the values of individual option settings for the dassl, fsolve, lsode, npsol, qpsol, and quad functions using commands like dassl_reltol = dassl_options ("relative tolerance"); * The svd() function no longer computes the left and right singular matrices unnecessarily. This can significantly improve performance for large matrices if you are just looking for the singular values. * The filter() function is now a built-in function. * New function randn() returns a pseudo-random number from a normal distribution. The rand() and randn() functions have separate seeds and generators. * Octave's command-line arguments are now available in the built-in variable `argv'. The program name is also available in the variables `program_invocation_name' and `program_name'. If executing a script from the command line (e.g., octave foo.m) or using the `#! /bin/octave' hack, the program name is set to the name of the script. * New built-in variable `completion_append_char' used as the character to append to successful command-line completion attempts. The default is " " (a single space). * Octave now uses a modified copy of the readline library from version 1.14.5 of GNU bash. * In prompt strings, `\H' expands to the whole host name. * New built-in variable `beep_on_error'. If nonzero, Octave will try to ring your terminal's bell before printing an error message. The default value is 0. * For functions defined from files, the type command now prints the text of the file. You can still get the text reconstructed from the parse tree by using the new option -t (-transformed). * New command-line argument --traditional sets the following preference variables for compatibility with Matlab: PS1 = ">> " PS2 = "" beep_on_error = 1 default_save_format = "mat-binary" define_all_return_values = 1 do_fortran_indexing = 1 empty_list_elements_ok = 1 implicit_str_to_num_ok = 1 ok_to_lose_imaginary_part = 1 page_screen_output = 0 prefer_column_vectors = 0 prefer_zero_one_indexing = 1 print_empty_dimensions = 0 treat_neg_dim_as_zero = 1 warn_function_name_clash = 0 whitespace_in_literal_matrix = "traditional" * New functions: readdir -- returns names of files in directory as array of strings mkdir -- create a directory rmdir -- remove a directory rename -- rename a file unlink -- delete a file umask -- set permission mask for file creation stat -- get information about a file lstat -- get information about a symbolic link glob -- perform filename globbing fnmatch -- match strings with filename globbing patterns more -- turn the pager on or off gammaln -- alias for lgamma * New audio functions from Andreas Weingessel . lin2mu -- linear to mu-law encoding loadaudio -- load an audio file to a vector mu2lin -- mu-law to linear encoding playaudio -- play an audio file record -- record sound and store in vector saveaudio -- save a vector as an audio file setaudio -- executes mixer shell command * New plotting functions from Vinayak Dutt. Ones dealing with multiple plots on one page require features from gnuplot 3.6beta (or later). bottom_title -- put title at the bottom of the plot mplot -- multiplot version of plot multiplot -- switch multiple-plot mode on or off oneplot -- return to one plot per page plot_border -- put a border around plots subplot -- position multiple plots on a single page subwindow -- set subwindow position for next plot top_title -- put title at the top of the plot zlabel -- put a label on the z-axis * New string functions bin2dec -- convert a string of ones and zeros to an integer blanks -- create a string of blanks deblank -- delete trailing blanks dec2bin -- convert an integer to a string of ones and zeros dec2hex -- convert an integer to a hexadecimal string findstr -- locate occurrences of one string in another hex2dec -- convert a hexadecimal string to an integer index -- return position of first occurrence a string in another rindex -- return position of last occurrence a string in another split -- divide one string into pieces separated by another str2mat -- create a string matrix from a list of strings strrep -- replace substrings in a string substr -- extract a substring The following functions return a matrix of ones and zeros. Elements that are nonzero indicate that the condition was true for the corresponding character in the string array. isalnum -- letter or a digit isalpha -- letter isascii -- ascii iscntrl -- control character isdigit -- digit isgraph -- printable (but not space character) islower -- lower case isprint -- printable (including space character) ispunct -- punctuation isspace -- whitespace isupper -- upper case isxdigit -- hexadecimal digit These functions return new strings. tolower -- convert to lower case toupper -- convert to upper case * New function, fgetl. Both fgetl and fgets accept an optional second argument that specifies a maximum number of characters to read, and the function fgets is now compatible with Matlab. * Printing in hexadecimal format now works (format hex). It is also possible to print the internal bit representation of a value (format bit). Note that these formats are only implemented for numeric values. * Additional structure features: -- Name completion now works for structures. -- Values and names of structure elements are now printed by default. The new built-in variable `struct_levels_to_print' controls the depth of nested structures to print. The default value is 2. -- New functions: struct_contains (S, NAME) -- returns 1 if S is a structure with element NAME; otherwise returns 0. struct_elements (S) -- returns the names of all elements of structure S in an array of strings. * New io/subprocess functions: fputs -- write a string to a file with no formatting popen2 -- start a subprocess with 2-way communication mkfifo -- create a FIFO special file popen -- open a pipe to a subprocess pclose -- close a pipe from a subprocess waitpid -- check the status of or wait for subprocesses * New time functions: asctime -- format time structure according to local format ctime -- equivalent to `asctime (localtime (TMSTRUCT))' gmtime -- return time structure corresponding to UTC localtime -- return time structure corresponding to local time zone strftime -- print given time structure using specified format time -- return current time The `clock' and `date' functions are now implemented in M-files using these basic functions. * Access to additional Unix system calls: dup2 -- duplicate a file descriptor exec -- replace current process with a new process fcntl -- control open file descriptors fork -- create a copy of the current process getpgrp -- return the process group id of the current process getpid -- return the process id of the current process getppid -- return the process id of the parent process getuid -- return the real user id of the current process getgid -- return the real group id of the current process geteuid -- return the effective user id of the current process getegid -- return the effective group id of the current process pipe -- create an interprocess channel * Other new functions: commutation_matrix -- compute special matrix form duplication_matrix -- compute special matrix form common_size.m -- bring arguments to a common size completion_matches -- perform command completion on string tilde_expand -- perform tilde expansion on string meshgrid -- compatible with Matlab's meshgrid function tmpnam -- replaces octave_tmp_file_name atexit -- register functions to be called when Octave exits putenv -- define an environment variable bincoeff -- compute binomial coefficients nextpow2 -- compute the next power of 2 greater than a number detrend -- remove a best fit polynomial from data erfinv -- inverse error function shift -- perform a circular shift on the elements of a matrix pow2 -- compute 2 .^ x log2 -- compute base 2 logarithms diff -- compute differences of matrix elements vech -- stack columns of a matrix below the diagonal vec -- stack columns of a matrix to form a vector xor -- compute exclusive or * Functions for getting info from the password database on Unix systems: getpwent -- read entry from password-file stream, opening if necessary getpwuid -- search for password entry with matching user ID getpwnam -- search for password entry with matching username setpwent -- rewind the password-file stream endpwent -- close the password-file stream * Functions for getting info from the group database on Unix systems: getgrent -- read entry from group-file stream, opening if necessary getgrgid -- search for group entry with matching group ID getgrnam -- search for group entry with matching group name setgrent -- rewind the pgroup-file stream endgrent -- close the group-file stream * The New function octave_config_info returns a structure containing information about how Octave was configured and compiled. * New function getrusage returns a structure containing system resource usage statistics. The `cputime' function is now defined in an M-file using getrusage. * The info reader is now a separate binary that runs as a subprocess. You still need the info reader distributed with Octave though, because there are some new command-line arguments that are not yet available in the public release of Info. * There is a new built-in variable, INFO_PROGRAM, which is used as the name of the info program to run. Its initial value is $OCTAVE_HOME/lib/octave/VERSION/exec/ARCH/info, but that value can be overridden by the environment variable OCTAVE_INFO_PROGRAM, or the command line argument --info-program NAME, or by setting the value of INFO_PROGRAM in a startup script. * There is a new built-in variable, EXEC_PATH, which is used as the list of directories to search when executing subprograms. Its initial value is taken from the environment variable OCTAVE_EXEC_PATH (if it exists) or PATH, but that value can be overridden by the the command line argument --exec-path PATH, or by setting the value of EXEC_PATH in a startup script. If the EXEC_PATH begins (ends) with a colon, the directories $OCTAVE_HOME/lib/octave/VERSION/exec/ARCH and $OCTAVE_HOME/bin are prepended (appended) to EXEC_PATH (if you don't specify a value for EXEC_PATH explicitly, these special directories are prepended to your PATH). * If it is present, Octave will now use an `ls-R' database file to speed up recursive path searching. Octave looks for a file called ls-R in the directory specified by the environment variable OCTAVE_DB_DIR. If that is not set but the environment variable OCTAVE_HOME is set, Octave looks in $OCTAVE_HOME/lib/octave. Otherwise, Octave looks in the directory $datadir/octave (normally /usr/local/lib/octave). * New examples directory. * There is a new script, mkoctfile, that can be used to create .oct files suitable for dynamic linking. * Many more bug fixes. * ChangeLogs are now kept in each subdirectory. See NEWS.1 for old news.