Preliminary inclusion of uixx objects properties in the manual (bug #46076) * doc/interpreter/genpropdoc.m: add uixx objects to the list of supported graphics objects * doc/interpreter/genpropdoc.m (get_doc): add uixx objects and their specific properties (currently empty documentation) * doc/interpreter/plot.txi("Interacting with Plots"): add a note and a reference about ui* family of functions. * doc/interpreter/plot.txi("Interacting with Plots"): for consistency, remove "uimenu" reference. All the other uixx are already in the gui section * doc/interpreter/plot.txi("graphics data structure"): add uixx objects * doc/interpreter/gui.txi("UI Elements"): add "uimenu" function reference * doc/module.mk: add rules to build uixx properties texi files. * graphics.in.h: make uixx "__object__" property (Octave internal) hidden so that it does not appear in the documentation.

{ x[NR] = $0; } END {
  print "@multitable @columnfractions .33 .33 .33";
  rem = NR % 3;
  n = NR - rem;
  for (i = 1; i <= n; i += 3)
    printf ("@item %s @tab %s @tab %s\n", x[i], x[i+1], x[i+2]);
  if (rem == 1)
    printf ("@item %s\n", x[NR]);
  else if (rem == 2)
    printf ("@item %s @tab %s\n", x[NR-1], x[NR]);
  print "@end multitable";
}