May 23, 2015
** A graphical user interface is now the default when running Octave interactively. The start-up option --no-gui will run the familiar command line interface, and still allows use of the GUI dialogs and qt plotting toolkit. The option --no-gui-libs runs a minimalist command line interface that does not link with the Qt libraries and uses the fltk toolkit for plotting. ** Octave now uses OpenGL graphics with Qt widgets by default. If OpenGL libraries are not available when Octave is built, gnuplot is used. You may choose to use the fltk or gnuplot toolkit for graphics by executing the command graphics_toolkit ("fltk") OR graphics_toolkit ("gnuplot") Adding such a command to your ~/.octaverc file will set the default for each session. ** A new syntax for object oriented programming termed classdef has been introduced. See the manual for more extensive documentation of the classdef interface. New keywords: classdef endclassdef enumeration endenumeration events endevents methods endmethods properties endproperties ** New audio functions and classes: audiodevinfo audioread sound audioinfo audiorecorder soundsc audioplayer audiowrite ** Other new classes in Octave 4.0: audioplayer inputParser audiorecorder ** Optional stricter Matlab compatibility for ranges, diagonal matrices, and permutation matrices. Octave has internal optimizations which use space-efficient storage for the three data types above. Three new functions have been added which control whether the optimizations are used (default), or whether the data types are stored as full matrices. disable_range disable_diagonal_matrix disable_permutation_matrix All three optimizations are disabled if Octave is started with the --braindead command line option. ** The preference do_braindead_shortcircuit_evaluation is now enabled by default. ** The preference allow_noninteger_range_as_index is now enabled by default and the warning ID Octave:noninteger-range-as-index is now set to "on" by default instead of "error" by default and "on" for --traditional. ** The "backtrace" warning option is now enabled by default. This change was made for Matlab compatibility. ** For compatibility with Matlab, the "ismatrix (x)" function now only checks the dimension of "x". The old behaviour of "ismatrix" is obtained by "isnumeric (x) || islogical (x) || ischar (x)". ** The nextpow2 function behaviour has been changed for vector inputs. Instead of computing `nextpow2 (length (x))', it will now compute nextpow2 for each element of the input. This change is Matlab compatible, and also prevents bugs for "vectors" of length 1. ** polyeig now returns a row vector of eigenvalues rather than a matrix with the eigenvalues on the diagonal. This change was made for Matlab compatibility. ** Interpolation function changes for Matlab compatibility The interpolation method 'cubic' is now equivalent to 'pchip' for interp1, interp2, and interp3. Previously, 'cubic' was equivalent to 'spline' for interp2. This may produce different results as 'spline' has continuous 1st and 2nd derivatives while 'pchip' only has a continuous 1st derivative. The methods 'next' and 'previous' have been added to interp1 for compatibility. ** The delaunay function has been extended to accept 3-D inputs for Matlab compatibility. The delaunay function no longer plots the triangulation if no output argument is requested, instead, the triangulation is always returned. The delaunay3 function which handles 3-D inputs has been deprecated in favor of delaunay. ** The trigonometric functions asin and acos return different phase values from previous versions of Octave when the input is outside the principal branch ([-1, 1]). If the real portion of the input is greater than 1 then the limit from below is taken. If the real portion is less than 1 then the limit from above is taken. This criteria is consistent with several other numerical analysis software packages. ** The hyperbolic function acosh now returns values with a phase in the range [-pi/2, +pi/2]. Previously Octave returned values in the range [0, pi]. This is consistent with several other numerical analysis software packages. ** strfind changes when using empty pattern ("") for Matlab compatibility strfind now returns an empty array when the pattern itself is empty. In previous versions of Octave, strfind matched at every character location when the pattern was empty. NEW strfind ("abc", "") =>  OLD strfind ("abc", "") => [1, 2, 3, 4] ** Integer formats used in the printf family of functions now work for 64-bit integers and are more compatible with Matlab when printing non-integer values. Now instead of truncating, Octave will switch the effective format to '%g' in the following circumstances: * the value of an integer type (int8, uint32, etc.) value exceeds the maximum for the format specifier. For '%d', the limit is intmax ('int64') and for '%u' it is intmax ('uint64'). * round(x) != x or the value is outside the range allowed by the integer format specifier. There is still one difference: Matlab switches to '%e' and Octave switches to '%g'. ** The functions intersect, setdiff, setxor, and union now return a column vector as output unless the input was a row vector. This change was made for Matlab compatibility. ** The inpolygon function now returns true for points that are within the polygon OR on it's edge. This change was made for Matlab compatibility. ** The archive family of functions (bzip2, gzip, zip, tar) and their unpacking routines (bunzip2, gunzip, unzip, untar, unpack) have been recoded. Excepting unpack, the default is now to place files in the same directory as the archive (on unpack) or as the original files (on archiving). ** Qt and FLTK graphics toolkits now support offscreen rendering on Linux. In other words, print will work even when the figure visibility is "off". ** Z-order stacking issues with patches, grid lines, and line object plot markers for on screen display and printing have all been resolved. For 2-D plots the axis grid lines can be placed on top of the plot with set (gca, "layer", "top"). ** The patch graphic object has been overhauled. It now produces visual results equivalent to Matlab even for esoteric combinations of faces/vertices/cdata. ** The polar() plot function now draws a circular theta axis and radial rho axis rather than using a rectangular x/y axis. ** linkprop has been completely re-coded for performance and Matlab compatibility. It now returns a linkprop object which must be stored in a variable for as long as the graphic objects should remain linked. To unlink properties use 'clear hlink' where hlink is the variable containing the linkprop object. ** isprime has been extended to operate on negative and complex inputs. ** xor has been extended to accept more than two arguments in which case it performs cumulative XOR reduction. ** The following functions now support N-dimensional arrays: fliplr flipud rot90 rectint ** The new warning ID "Octave:data-file-in-path" replaces the three previous separate warning IDs "Octave:fopen-file-in-path", "Octave:load-file-in-path", and "Octave:md5sum-file-in-path". ** The warning ID Octave:singular-matrix-div has been replaced by Octave:nearly-singular-matrix and Octave:singular-matrix. ** The warning ID Octave:matlab-incompatible has been replaced by Octave:language-extension to better reflect its meaning. ** The warning ID Octave:broadcast has been removed. Instead automatic broadcasting will throw an Octave:language-extension warning. This warning ID is used for broadcasting as well as other features not available in Matlab. ** Other new functions added in 4.0: annotation bandwidth cubehelix dir_in_loadpath flip frame2im get_home_directory hgload hgsave ichol ilu im2frame isbanded isdiag isstudent istril istriu javachk jit_failcnt linkaxes lscov metaclass numfields open ordschur pan qmr rotate rotate3d sylvester unsetenv validateattributes zoom ** inline() scheduled for eventual deprecation by Matlab Functions created through the use of inline are scheduled for deprecation by Matlab. When this occurs Octave will continue to support inline functions for an indeterminate amount of time before also removing support. All new code should use anonymous functions in place of inline functions. ** Deprecated functions. The following functions have been deprecated in Octave 4.0 and will be removed from Octave 4.4 (or whatever version is the second major release after 4.0): Function | Replacement ---------------------|------------------ bicubic | interp2 delaunay3 | delaunay dump_prefs | individual preference get/set routines find_dir_in_path | dir_in_loadpath finite | isfinite fmod | rem fnmatch | glob or regexp loadaudio | audioread luinc | ilu or ichol mouse_wheel_zoom | mousewheelzoom axes property nfields | numfields octave_tmp_file_name | tempname playaudio | audioplayer saveaudio | audiowrite syl | sylvester usage | print_usage allow_noninteger_range_as_index do_braindead_shortcircuit_evaluation setaudio ** The following functions were deprecated in Octave 3.8 and will be removed from Octave 4.2 (or whatever version is the second major release after 3.8): default_save_options java_new gen_doc_cache java_unsigned_conversion interp1q javafields isequalwithequalnans javamethods java_convert_matrix re_read_readline_init_file java_debug read_readline_init_file java_invoke saving_history ** The following functions were deprecated in Octave 3.6 and have been removed from Octave 4.0. cut polyderiv cor shell_cmd corrcoef studentize __error_text__ sylvester_matrix error_text ** The following keywords were deprecated in Octave 3.8 and have been removed from Octave 4.0 static ** The following configuration variables were deprecated in Octave 3.8 and have been removed from Octave 4.0 CC_VERSION (now GCC_VERSION) CXX_VERSION (now GXX_VERSION) ** The internal function atan2 of the sparse matrix class has been deprecated in Octave 4.0 and will be removed from Octave 4.4 (or whatever version is the second major release after 4.0). Use the Fatan2 function with sparse inputs as a replacement. ** The internal class Octave_map was deprecated in Octave 3.8 and has been removed from Octave 4.0. Replacement classes are octave_map (struct array) or octave_scalar_map for a single structure. ** The configure option --enable-octave-allocator has been removed. The internal class octave_allocator declared in oct-alloc.h has been removed. The header remains, but is deprecated. The macros to access the class (DECLARE_OCTAVE_ALLOCATOR, DEFINE_OCTAVE_ALLOCATOR, and DEFINE_OCTAVE_ALLOCATOR2) are now unconditionally defined to be empty. ** Octave now has OpenMP enabled by default if the system provides a working OpenMP implementation. This allows oct-file modules to take advantage of OpenMP if desired. This can be disabled when building Octave with the configure option --disable-openmp. ** Octave now automatically truncates intermediate calculations done with floating point values to 64 bits. Some hardware math co-processors, such as the x87, maintain extra precision, but this leads to disagreements in calculations when compared to reference implementations in software using the IEEE standard for double precision. There was no measurable performance impact to this change, but it may be disabled with the configure option --disable-float-truncate. MinGW and Cygwin platforms, as well as GCC compilers >= 5.0 require this feature. Non-x87 hardware, or hardware using SSE options exclusively, can disable float truncation if desired.