Use upper/lower in preference to toupper/tolower to match Matlab. * mappers.cc (Fupper, Flower): Functions renamed from toupper/tolower and now use "DEFUN" macro. Change DEFALIAS to correctly map toXXX to XXX. Update all BIST tests. * func.txi, strings.txi: Update manual. * cellfun.cc, utils.cc, Map.m, idivide.m, integral.m, integral2.m, integral3.m, interp1.m, quad2d.m, quadgk.m, rng.m, griddata.m, griddatan.m, listdlg.m, movegui.m, __file_filter__.m, uigetfile.m, uisetfont.m, __unimplemented__.m, colormap.m, imformats.m, imshow.m, __imread__.m, __imwrite__.m, rgbplot.m, javaclasspath.m, genvarname.m, edit.m, inputParser.m, license.m, open.m, parseparams.m, unpack.m, validateattributes.m, __all_opts__.m, get_description.m, get_forge_pkg.m, camorbit.m, daspect.m, datetick.m, pbaspect.m, __tickangle__.m, rticks.m, thetaticks.m, xticks.m, yticks.m, zticks.m, camlight.m, colorbar.m, isocaps.m, isosurface.m, __add_datasource__.m, __patch__.m, __scatter__.m, reducepatch.m, smooth3.m, surfl.m, hgload.m, hold.m, openfig.m, __add_default_menu__.m, __print_parse_opts__.m, refreshdata.m, saveas.m, struct2hdl.m, movfun.m, stft.m, eigs.m, ichol.m, ilu.m, gammainc.m, gallery.m, corrcoef.m, iqr.m, normalize.m, base2dec.m, index.m, regexptranslate.m, strsplit.m, datestr.m, mk-sparse-tst.sh: Replace toupper/tolower with upper/lower in Octave code.

--- a/scripts/image/imformats.m	Wed Apr 12 14:40:52 2023 -0700
+++ b/scripts/image/imformats.m	Wed Apr 12 15:34:43 2023 -0700
@@ -89,7 +89,7 @@
       formats = arg1;
 
     elseif (ischar (arg1))
-      switch (tolower (arg1))
+      switch (lower (arg1))
         case "add",
           if (! isstruct (arg2))
             error ("imformats: FORMAT to %s must be a structure", arg1);