doc: Use XREF as anchor prefix in documentation for clearer results in Info viewer. Correctly use @xref, @pxref, @ref macros in documentation. * doc/interpreter/arith.txi, doc/interpreter/basics.txi, doc/interpreter/container.txi, doc/interpreter/debug.txi, doc/interpreter/diagperm.txi, doc/interpreter/eval.txi, doc/interpreter/external.txi, doc/interpreter/func.txi, doc/interpreter/install.txi, doc/interpreter/interp.txi, doc/interpreter/intro.txi, doc/interpreter/java.txi, doc/interpreter/matrix.txi, doc/interpreter/munge-texi.pl, doc/interpreter/numbers.txi, doc/interpreter/package.txi, doc/interpreter/plot.txi, doc/interpreter/sparse.txi, doc/interpreter/stats.txi, doc/interpreter/strings.txi, doc/interpreter/system.txi, doc/interpreter/var.txi, doc/interpreter/vectorize.txi, libinterp/corefcn/error.cc, libinterp/corefcn/qz.cc, libinterp/corefcn/regexp.cc, scripts/general/accumarray.m, scripts/general/structfun.m, scripts/miscellaneous/edit.m, scripts/miscellaneous/setfield.m, scripts/miscellaneous/warning_ids.m, scripts/optimization/fminbnd.m, scripts/optimization/fzero.m, scripts/optimization/lsqnonneg.m: Use XREF as anchor prefix in documentation for clearer results in Info viewer. Correctly use @xref, @pxref, @ref macros in documentation. * scripts/plot/line.m: Remove extra ')' in @deftypefn. * libgui/src/qtinfo/parser.cc(find_ref): Change doc anchor search pattern to XREF.

--- a/scripts/general/accumarray.m
+++ b/scripts/general/accumarray.m
@@ -61,7 +61,7 @@
 ## that in the first column counts how many occurrences each number in
 ## the second column has, taken from the vector @var{x}.  Note the usage
 ## of @code{unique}  for assigning to all repeated elements of @var{x}
-## the same index (@pxref{docXunique}).
+## the same index (@pxref{XREFunique,,unique}).
 ##
 ## @example
 ## @group
@@ -92,7 +92,7 @@
 ## @end example
 ##
 ## The sparse option can be used as an alternative to the @code{sparse}
-## constructor (@pxref{docXsparse}).  Thus
+## constructor (@pxref{XREFsparse,,sparse}).  Thus
 ##
 ## @example
 ## sparse (@var{i}, @var{j}, @var{sv})