--- a/NEWS	Wed Sep 14 12:45:52 2016 -0700
+++ b/NEWS	Wed Sep 14 13:19:47 2016 -0700
@@ -16,6 +16,8 @@
 
     Examples: 0b101 == 5  or  0B1100_0001 == 0xC1
 
+ ** gnuplot 4.4 is now the minimum version supported by Octave.
+
  ** The default set of colors used to plot lines has been updated to be
     compatible with Matlab's new default color scheme.  The line plot
     color scheme can be set with the axes property "ColorOrder".

--- a/etc/README.MacOS	Wed Sep 14 12:45:52 2016 -0700
+++ b/etc/README.MacOS	Wed Sep 14 13:19:47 2016 -0700
@@ -222,7 +222,7 @@
   fltk-aqua-shlibs
   glpk-dev
   glpk-shlibs
-  gnuplot (>= 4.2.6)
+  gnuplot (>= 4.4)
   graphicsmagick (<= 1.3.7)
   graphicsmagick-shlibs (<= 1.3.7)
   hdf5 (>= 1.6.5)

--- a/etc/README.gnuplot	Wed Sep 14 12:45:52 2016 -0700
+++ b/etc/README.gnuplot	Wed Sep 14 13:19:47 2016 -0700
@@ -1,12 +1,7 @@
-Octave works best with gnuplot 4.4 or higher, which is available from
+Octave requires gnuplot 4.4 or higher, which is available from
 http://www.gnuplot.info.
 
-In versions prior to 4.2.6 it is not possible to use the mouse to zoom in
-on plots.  This is a limitation of earlier versions of gnuplot, which are
-unable to zoom when the data it plots is not stored in a file.
-
-
 John W. Eaton
 jwe@octave.org
 
-Last updated: Tue Jan  4 18:55:56 PST 2011
+Last updated: Wed Sep 14 12:25:25 PDT 2016

--- a/scripts/image/image.m	Wed Sep 14 12:45:52 2016 -0700
+++ b/scripts/image/image.m	Wed Sep 14 13:19:47 2016 -0700
@@ -32,8 +32,6 @@
 ## convenience, @var{x} and @var{y} may be specified as N-element vectors
 ## matching the length of the data in @var{img}.  However, only the first and
 ## last elements will be used to determine the axis limits.
-## @strong{Warning:} @var{x} and @var{y} are ignored when using gnuplot 4.0
-## or earlier.
 ##
 ## Multiple property/value pairs may be specified for the image object, but
 ## they must appear in pairs.
@@ -133,8 +131,7 @@
 ## Generic image creation.
 ##
 ## The axis values corresponding to the matrix elements are specified in
-## @var{x} and @var{y}.  If you're not using gnuplot 4.2 or later, these
-## variables are ignored.
+## @var{x} and @var{y}.
 
 ## Author: Tony Richardson <arichard@stark.cc.oh.us>
 ## Created: July 1994

--- a/scripts/plot/draw/private/__bar__.m	Wed Sep 14 12:45:52 2016 -0700
+++ b/scripts/plot/draw/private/__bar__.m	Wed Sep 14 13:19:47 2016 -0700
@@ -27,8 +27,7 @@
 
   [hax, varargin, nargin] = __plt_get_axis_arg__ (func, varargin{:});
 
-  ## Slightly smaller than 0.8 to avoid clipping issue in gnuplot 4.0
-  width = 0.8 - 10 * eps;
+  width = 0.8;
   group = true;
   histc = NA;
   bv = 0;  # BaseValue

--- a/scripts/plot/draw/private/__quiver__.m	Wed Sep 14 12:45:52 2016 -0700
+++ b/scripts/plot/draw/private/__quiver__.m	Wed Sep 14 13:19:47 2016 -0700
@@ -259,7 +259,6 @@
       h3 = plot (x, y, "linestyle", "none", "marker", mk, "parent", hg);
     endif
     if (have_filled)
-      ## FIXME: gnuplot doesn't respect the markerfacecolor field
       set (h3, "markerfacecolor", get (h1, "color"));
     endif
 

--- a/scripts/plot/util/__gnuplot_drawnow__.m	Wed Sep 14 12:45:52 2016 -0700
+++ b/scripts/plot/util/__gnuplot_drawnow__.m	Wed Sep 14 13:19:47 2016 -0700
@@ -193,16 +193,8 @@
                                  "epscairo", "epslatex", "fig", "gif", ...
                                  "jpeg", "latex", "pbm", "pdf", "pdfcairo", ...
                                  "postscript", "png", "pngcairo", "pstex", ...
-                                 "pslatex", "svg", "tikz"};
-          if (__gnuplot_has_feature__ ("windows_figure_position"))
-            terminals_with_size{end+1} = "windows";
-          endif
-          if (__gnuplot_has_feature__ ("x11_figure_position"))
-            terminals_with_size{end+1} = "x11";
-          endif
-          if (__gnuplot_has_feature__ ("wxt_figure_size"))
-            terminals_with_size{end+1} = "wxt";
-          endif
+                                 "pslatex", "svg", "tikz", "windows", ...
+                                 "wxt", "x11"};
           switch (term)
             case terminals_with_size
               size_str = sprintf ("size %.12g,%.12g", gnuplot_size);
@@ -228,10 +220,7 @@
             otherwise
               size_str = "";
           endswitch
-          if ((strcmp (term, "x11")
-               && __gnuplot_has_feature__ ("x11_figure_position"))
-              || (strcmpi (term, "windows")
-                  && __gnuplot_has_feature__ ("windows_figure_position")))
+          if (strcmp (term, "x11") || strcmpi (term, "windows"))
             ## X11/Windows allows the window to be positioned as well.
             units = get (0, "units");
             unwind_protect
@@ -300,16 +289,6 @@
         term_str = [term_str " " size_str];
       endif
     endif
-    if (! __gnuplot_has_feature__ ("has_termoption_dashed"))
-      ## If "set termoption dashed" isn't available add "dashed" option
-      ## to the "set terminal ..." command, if it is supported.
-      if (any (strcmp (term, {"aqua", "cgm", "eepic", "emf", "epslatex", ...
-                              "fig", "pcl5", "mp", "next", "openstep", ...
-                              "pdf", "pdfcairo", "pngcairo", "postscript", ...
-                              "pslatex", "pstext", "svg", "tgif", "x11"})))
-        term_str = [term_str " dashed"];
-      endif
-    endif
     if (any (strcmp (term, {"aqua", "wxt"})))
       term_str = [term_str, " ", "dashlength 1"];
     elseif (any (strcmp (term, {"epslatex", "postscript", "pslatex"})))
@@ -339,8 +318,7 @@
         endif
       endif
     endif
-    if (__gnuplot_has_feature__ ("has_termoption_dashed")
-        && ! __gnuplot_has_feature__ ("dashtype"))
+    if (! __gnuplot_has_feature__ ("dashtype"))
       fprintf (plot_stream, "set termoption dashed\n");
     endif
   else

--- a/scripts/plot/util/graphics_toolkit.m	Wed Sep 14 12:45:52 2016 -0700
+++ b/scripts/plot/util/graphics_toolkit.m	Wed Sep 14 13:19:47 2016 -0700
@@ -82,8 +82,6 @@
   endif
 
   if (! any (strcmp (loaded_graphics_toolkits (), name)))
-    ## FIXME: Special gnuplot handling for versions < 4.2.5 (bug #44978).
-    ## This can probably be deleted in the future once RHEL upgrades gnuplot.
     if (strcmp (name, "gnuplot"))
       valid_version = __gnuplot_has_feature__ ("minimum_version");
       if (valid_version != 1)

--- a/scripts/plot/util/private/__gnuplot_draw_axes__.m	Wed Sep 14 12:45:52 2016 -0700
+++ b/scripts/plot/util/private/__gnuplot_draw_axes__.m	Wed Sep 14 13:19:47 2016 -0700
@@ -83,43 +83,21 @@
   endif
 
   if (strcmp (axis_obj.activepositionproperty, "position"))
-    if (__gnuplot_has_feature__ ("screen_coordinates_for_{lrtb}margin"))
-      if (nd == 2 || all (mod (axis_obj.view, 90) == 0))
-        x = [1, 1];
-      else
-        ## 3D plots need to be sized down to fit in the window.
-        x = 1.0 ./ sqrt ([2, 2.5]);
-      endif
-      fprintf (plot_stream, "set tmargin screen %.15g;\n",
-               pos(2)+pos(4)/2+x(2)*pos(4)/2);
-      fprintf (plot_stream, "set bmargin screen %.15g;\n",
-               pos(2)+pos(4)/2-x(2)*pos(4)/2);
-      fprintf (plot_stream, "set lmargin screen %.15g;\n",
-               pos(1)+pos(3)/2-x(1)*pos(3)/2);
-      fprintf (plot_stream, "set rmargin screen %.15g;\n",
-               pos(1)+pos(3)/2+x(1)*pos(3)/2);
-      sz_str = "";
+    if (nd == 2 || all (mod (axis_obj.view, 90) == 0))
+      x = [1, 1];
     else
-      fprintf (plot_stream, "set tmargin 0;\n");
-      fprintf (plot_stream, "set bmargin 0;\n");
-      fprintf (plot_stream, "set lmargin 0;\n");
-      fprintf (plot_stream, "set rmargin 0;\n");
-
-      if (nd == 3 && all (axis_obj.view == [0, 90]))
-        ## FIXME: Kludge to allow colorbar to be added to a pcolor() plot
-        pos(3:4) = pos(3:4) * 1.4;
-        pos(1:2) = pos(1:2) - pos(3:4) * 0.125;
-      endif
-
-      fprintf (plot_stream, "set origin %.15g, %.15g;\n", pos(1), pos(2));
-
-      if (strcmp (axis_obj.dataaspectratiomode, "manual"))
-        sz_str = sprintf ("set size ratio %.15g", -dr);
-      else
-        sz_str = "set size noratio";
-      endif
-      sz_str = sprintf ("%s %.15g, %.15g;\n", sz_str, pos(3), pos(4));
+      ## 3D plots need to be sized down to fit in the window.
+      x = 1.0 ./ sqrt ([2, 2.5]);
     endif
+    fprintf (plot_stream, "set tmargin screen %.15g;\n",
+             pos(2)+pos(4)/2+x(2)*pos(4)/2);
+    fprintf (plot_stream, "set bmargin screen %.15g;\n",
+             pos(2)+pos(4)/2-x(2)*pos(4)/2);
+    fprintf (plot_stream, "set lmargin screen %.15g;\n",
+             pos(1)+pos(3)/2-x(1)*pos(3)/2);
+    fprintf (plot_stream, "set rmargin screen %.15g;\n",
+             pos(1)+pos(3)/2+x(1)*pos(3)/2);
+    sz_str = "";
   else ## activepositionproperty == outerposition
     fprintf (plot_stream, "unset tmargin;\n");
     fprintf (plot_stream, "unset bmargin;\n");
@@ -885,8 +863,7 @@
                                      [[xcol; xcol(end)], [ycol; ycol(end)], ...
                                      [zcol; zcol(end)], [ccdat; ccdat(end)]]'];
               else
-                if (__gnuplot_has_feature__ ("transparent_patches")
-                        && isscalar (obj.facealpha))
+                if (isscalar (obj.facealpha))
                   colorspec = sprintf ("lc rgb \"#%02x%02x%02x\" fillstyle transparent solid %f",
                                        round (255*color), obj.facealpha);
                 else
@@ -937,8 +914,7 @@
                 ec = obj.edgecolor;
               endif
 
-              if ((strcmp (ec, "flat")
-                   || strcmp (ec, "interp"))
+              if ((strcmp (ec, "flat") || strcmp (ec, "interp"))
                   && isfield (obj, "cdata"))
                 if (ndims (obj.cdata) == 2
                     && (columns (obj.cdata) == nc
@@ -1310,8 +1286,7 @@
             dord = "depthorder";
           endif
 
-          if (__gnuplot_has_feature__ ("transparent_surface")
-              && isscalar (obj.facealpha))
+          if (isscalar (obj.facealpha))
             fprintf (plot_stream,
                      "set style fill transparent solid %f;\n",
                      obj.facealpha);
@@ -1635,13 +1610,9 @@
       otherwise
         pos = "";
     endswitch
-    if (__gnuplot_has_feature__ ("key_has_font_properties"))
-      [fontname, fontsize] = get_fontname_and_size (hlgnd);
-      fontspacespec = [create_spacingspec(fontname, fontsize, gnuplot_term),...
-                       ' ', create_fontspec(fontname, fontsize, gnuplot_term)];
-    else
-      fontspacespec = "";
-    endif
+    [fontname, fontsize] = get_fontname_and_size (hlgnd);
+    fontspacespec = [create_spacingspec(fontname, fontsize, gnuplot_term),...
+                     ' ', create_fontspec(fontname, fontsize, gnuplot_term)];
     textcolors = get (findobj (hlgnd.children, "type", "text"), "color");
     if (iscell (textcolors))
       textcolors = cell2mat (textcolors);

--- a/scripts/plot/util/private/__gnuplot_has_feature__.m	Wed Sep 14 12:45:52 2016 -0700
+++ b/scripts/plot/util/private/__gnuplot_has_feature__.m	Wed Sep 14 13:19:47 2016 -0700
@@ -26,17 +26,6 @@
 
 function res = __gnuplot_has_feature__ (feature)
   persistent features = {"minimum_version",
-                         "x11_figure_position",
-                         "wxt_figure_size",
-                         "transparent_patches",
-                         "transparent_surface",
-                         "epslatex_implies_eps_filesuffix",
-                         "epslatexstandalone_terminal",
-                         "screen_coordinates_for_{lrtb}margin",
-                         "variable_GPVAL_TERMINALS",
-                         "key_has_font_properties",
-                         "windows_figure_position",
-                         "has_termoption_dashed",
                          "needs_color_with_postscript",
                          "linetype",
                          "dashtype",
@@ -50,8 +39,8 @@
       ## Don't throw an error if gnuplot isn't installed
       gnuplot_version = "0.0.0";
     end_try_catch
-    versions =  {"4.2.5", "4.2.5", "4.4", "4.4", "4.4", "4.2", "4.2", "4.4", "4.4", "4.4", "4.4", "4.3", "4.6", "4.6", "5.0", "4.6"};
-    operators = {   ">=",    ">=",  ">=",  ">=",  ">=",  ">=",  ">=",  ">=",  ">=",  ">=",  ">=",  ">=",  ">=",  ">=",  ">=",  ">="};
+    versions =  {"4.4", "4.6", "4.6", "5.0", "4.6"};
+    operators = {">=",  ">=",  ">=",  ">=",  ">="};
     have_features = false (size (features));
     for n = 1 : numel (have_features)
       has_features(n) = compare_versions (gnuplot_version, versions{n}, operators{n});

--- a/scripts/plot/util/private/__gnuplot_has_terminal__.m	Wed Sep 14 12:45:52 2016 -0700
+++ b/scripts/plot/util/private/__gnuplot_has_terminal__.m	Wed Sep 14 13:19:47 2016 -0700
@@ -29,34 +29,19 @@
   term = strtrim (term);
   term = lower (strtok (term, " "));
 
-  if (__gnuplot_has_feature__ ("variable_GPVAL_TERMINALS"))
-    if (nargin < 2)
-      plot_stream = __gnuplot_open_stream__ (2);
+  if (nargin < 2)
+    plot_stream = __gnuplot_open_stream__ (2);
+  endif
+  available_terminals = __gnuplot_get_var__ (plot_stream, "GPVAL_TERMINALS");
+  available_terminals = regexp (available_terminals, '\w+', "match");
+  if (nargin < 2 && ! isempty (plot_stream))
+    pclose (plot_stream(1));
+    if (numel (plot_stream) > 1)
+      pclose (plot_stream(2));
     endif
-    available_terminals = __gnuplot_get_var__ (plot_stream, "GPVAL_TERMINALS");
-    available_terminals = regexp (available_terminals, '\w+', "match");
-    if (nargin < 2 && ! isempty (plot_stream))
-      pclose (plot_stream(1));
-      if (numel (plot_stream) > 1)
-        pclose (plot_stream(2));
-      endif
-      if (numel (plot_stream) > 2)
-        waitpid (plot_stream(3));
-      endif
+    if (numel (plot_stream) > 2)
+      waitpid (plot_stream(3));
     endif
-  else
-    ## Gnuplot 4.0 terminals.  No new terminals were added until 4.4 which
-    ## allows the list of terminals to be obtained from GPVAL_TERMINALS.
-    available_terminals = {"aifm", "aqua", "canvas", "cgm", "corel", ...
-                           "dumb", "dxf", "eepic", "emf", "epslatex", ...
-                           "epson_180dpi", "fig", "gif", "gnugraph", ...
-                           "gpic", "hp2623A", "hp2648", "hp500c", ...
-                           "hpgl", "hpljii", "hppj", "imagen", "jpeg", ...
-                           "latex", "mf", "mif", "mp", "pbm", "pdf", ...
-                           "pm", "png", "postscript", "pslatex", ...
-                           "pstex", "pstricks", "qms", "regis", "rgip", ...
-                           "svg", "texdraw", "tgif", "tkcanvas", ...
-                           "tpic", "windows", "x11", "xlib", "xterm"};
   endif
 
   gnuplot_supports_term = any (strcmp (term, available_terminals));

--- a/scripts/plot/util/private/__gnuplot_print__.m	Wed Sep 14 12:45:52 2016 -0700
+++ b/scripts/plot/util/private/__gnuplot_print__.m	Wed Sep 14 13:19:47 2016 -0700
@@ -87,12 +87,7 @@
                "invalid suffix '%s' for device '%s'.",
                ext, lower (opts.devopt));
       endif
-      if (__gnuplot_has_feature__ ("epslatex_implies_eps_filesuffix"))
-        suffix = "tex";
-      else
-        ## Gnuplot 4.0 wants a ".eps" suffix.
-        suffix = "eps";
-      endif
+      suffix = "tex";
       if (strfind (opts.devopt, "standalone"))
         gp_opts = sprintf ("standalone %s", gp_opts);
         term = strrep (opts.devopt, "standalone", "");

--- a/scripts/plot/util/private/__print_parse_opts__.m	Wed Sep 14 12:45:52 2016 -0700
+++ b/scripts/plot/util/private/__print_parse_opts__.m	Wed Sep 14 13:19:47 2016 -0700
@@ -250,8 +250,7 @@
     __graphics_toolkit__ = get (0, "defaultfigure__graphics_toolkit__");
   endif
 
-  if (strcmp (__graphics_toolkit__, "gnuplot")
-      && __gnuplot_has_feature__ ("epslatex_implies_eps_filesuffix"))
+  if (strcmp (__graphics_toolkit__, "gnuplot"))
     suffixes(strncmp (dev_list, "epslatex", 8)) = {"eps"};
   endif