From owner-help-octave at bevo dot che dot wisc dot edu Fri Nov 3 00:29:01 1995 Subject: axis & randn From: John Eaton To: Jerry Lynch Cc: help-octave at bevo dot che dot wisc dot edu Date: Fri, 3 Nov 1995 00:29:00 -0600 Jerry Lynch wrote: : Just out of curiosity, are there any plans for some of the built-in : functions to be updated in the next release of octave to resemble Matlab : updates? For what it's worth, here are the new entries in the file since 1.1.1. These are things that are already mostly done, but some items will need addtional work. * 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. * 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'. * 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". * 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. It's initial value is determined by configure, but it 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. * 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 excteptions 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. * 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. * 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 umask -- set permission mask for file creation stat -- get information about a file lstat -- get information about a symbolic link more -- turn the pager on or off gammaln -- alias for lgamma * 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 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: XXX names of functions marked with `*' are subject to change * async_system -- start a subprocess asynchronously * execute -- 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 * sync_system -- start a subprocess synchronously unlink -- delete a file 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. * New function getrusage returns a structure containing system resource usage statistics. The `cputime' function is now defined in an M-file using getrusage. * 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). * Many more bug fixes. * ChangeLogs are now kept in each subdirectory. jwe