Summary of important user-visible changes for version 5.0 (yyyy-mm-dd):
----------------------------------------------------------------------

 ** The functions issymmetric and ishermitian accept an option "nonskew"
    or "skew" to calculate the symmetric or skew-symmetric property
    of a matrix.  Performance has also been increased.

 ** The issorted function now uses a direction option of "ascend" or
    "descend" to make it compatible with both the sort function and
    with Matlab.  Change all uses of "ascending" and "descending" in
    existing code to the new options.

 ** The strncmp and strncmpi functions now return true if the two input
    strings match, even though the number of characters specified by N
    exceeds the string length.  This behavior more closely matches
    common sense and is Matlab compatible.  Example:

      Octave 5.0 : strncmp ("abc", "abc", 100) => true
      Previously : strncmp ("abc", "abc", 100) => false

 ** The fsolve function has been tweaked to use larger step sizes when
    calculating the Jacobian of a function with finite differences.
    This leads to faster convergence.  The default solver options have
    also changed to be Matlab compatible.  This *may* result in existing
    code producing different results.

          Option     |  New Default   |  Old Default
      ------------------------------------------------
        FinDiffType  |   "forward"    |   "central"
        MaxFunEvals  | 100*length(x0) |     Inf
        TolFun       |     1e-6       |     1e-7
        TolX         |     1e-6       |     1e-7
        Updating     |     "off"      |     "on"

 ** The fminsearch function has changed default solver options for
    Matlab compatibility.  The accuracy option TolFun is now 1e-4 rather
    than 1e-7.  This *may* result in existing code producing different
    results.

 ** The fminbnd function has changed defaults for Matlab compatibility.
    This *may* result in existing code producing different results.

          Option     |  New Default   |  Old Default
      ------------------------------------------------
        MaxFunEvals  |      500       |     Inf
        MaxIter      |      500       |     Inf
        TolX         |     1e-4       |     1e-8

 ** Figure graphic objects have a new property "Number" which is
    read-only and will return the handle (number) of the figure.
    However, if the property "IntegerHandle" has been set to "off" then
    the property will return an empty matrix ([]).

 ** Printing using the -dtiff output device will now create compressed
    images using lzw compression.  This change was made for Matlab
    compatibility.  To produce uncompressed images use the -dtiffn
    device.

 ** The FFTW library is now required to perform FFT calculations.  The
    FFTPACK sources have been removed from Octave.

 ** The OSMesa library is no longer used.  To print invisible figures
    when using OpenGL graphics, the Qt QOFFSCREENSURFACE feature must be
    available and you must use the qt graphics toolkit.

 ** New functions added in 5.0:

      ordeig

 ** Legacy functions.

    The following functions have been declared legacy functions which
    means they are obsolete and should not be used in any new code.
    Unlike deprecated functions, however, their removal from Octave has
    not yet been scheduled.

      Function             | Replacement
      ---------------------|------------------
      findstr              | strfind
      flipdim              | flip
      isequalwithequalnans | isequaln
      isstr                | ischar
      setstr               | char
      strmatch             | strncmp or strcmp

 ** Deprecated functions.

    The following functions have been deprecated in Octave 5.0 and will
    be removed from Octave 7 (or whatever version is the second major
    release after 5.0):

      Function             | Replacement
      ---------------------|------------------
                           |

 ** The following functions were deprecated in Octave 4.2 and have been
    removed from Octave 5.0.

      Function             | Replacement
      ---------------------|------------------
      bitmax               | flintmax
      mahalanobis          | mahal in Octave-Forge statistics pkg
      md5sum               | hash
      octave_config_info   | __octave_config_info__
      onenormest           | normest1
      sleep                | pause
      usleep               | pause
      wavread              | audioread
      wavwrite             | audiowrite

 ** Deprecated graphics properties.

    The following properties or allowed corresponding values have been
    deprecated in Octave 5.0 and will be removed from Octave 7 (or whatever
    version is the second major release after 5.0):

      Object               | Property                | Value
      ---------------------|-------------------------|-------------------
                           |                         |

 ** The following properties or allowed corresponding values were
    deprecated in Octave 4.2 and have been removed from Octave 5.0:

      Object               | Property                | Value
      ---------------------|-------------------------|-------------------
      axes                 | xaxislocation           | "zero"
                           | yaxislocation           | "zero"
      patch                | normalmode              |
      surface              | normalmode              |

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