--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,7 @@
+2009-10-15  Jaroslav Hajek  <highegg@gmail.com>
+
+	* DLD-FUNCTIONS/lookup.cc (Flookup): Update docstring.
+
 2009-10-15  Jaroslav Hajek  <highegg@gmail.com>
 
 	* ov.h (octave_value::octave_value (octave_base_value *, bool)) : New constructor.

--- a/src/DLD-FUNCTIONS/lookup.cc
+++ b/src/DLD-FUNCTIONS/lookup.cc
@@ -142,13 +142,13 @@
 If table is increasing and @code{idx = lookup (table, y)}, then\n\
 @code{table(idx(i)) <= y(i) < table(idx(i+1))} for all @code{y(i)}\n\
 within the table.  If @code{y(i) < table (1)} then\n\
-@code{idx(i)} is 0. If @code{y(i) >= table(end)} then\n\
+@code{idx(i)} is 0. If @code{y(i) >= table(end)} or @code{isnan (y(i))} then\n\
 @code{idx(i)} is @code{n}.\n\
 \n\
 If the table is decreasing, then the tests are reversed.\n\
 For non-strictly monotonic tables, empty intervals are always skipped.\n\
 The result is undefined if @var{table} is not monotonic, or if\n\
-@b{any} of @var{table} or @var{y} contains a NaN.\n\
+@var{table} contains a NaN.\n\
 \n\
 The algorithm used by lookup is standard binary search, with optimizations\n\
 to speed up the case of arrays containing pre-ordered portions (sampling).\n\