# HG changeset patch
# User Mike Miller <mtmiller@octave.org>
# Date 1523861964 25200
# Node ID 316b75b0d886d982eef3557811231cc05dd60a5e
# Parent  32323f5e61d264b3a1efc63f6b8251fee7f189bb
restore find (false) to be compatible with Matlab again (bug #53655)

* find.cc (Ffind): Keep the dimensions of an empty logical result, so that
find (false) returns the correct size and shape.  Add related BISTs.

diff -r 32323f5e61d2 -r 316b75b0d886 libinterp/corefcn/find.cc
--- a/libinterp/corefcn/find.cc	Sun Apr 15 22:03:13 2018 -0700
+++ b/libinterp/corefcn/find.cc	Sun Apr 15 23:59:24 2018 -0700
@@ -446,7 +446,8 @@
 
           dim_vector dv = result.dims ();
 
-          retval(0) = (dv.isvector () ? result : result.reshape (dv.as_column ()));
+          retval(0) = (dv.all_zero () || dv.isvector ()
+                       ? result : result.reshape (dv.as_column ()));
         }
       else
         {
@@ -585,6 +586,11 @@
 %! assert (j, jfull);
 %! assert (all (v == 1));
 
+%!assert <*53655> (find (false), zeros (0, 0))
+%!assert <*53655> (find ([false, false]), zeros (1, 0))
+%!assert <*53655> (find ([false; false]), zeros (0, 1))
+%!assert <*53655> (find ([false, false; false, false]), zeros (0, 1))
+
 %!assert (find ([2 0 1 0 5 0], 1), 1)
 %!assert (find ([2 0 1 0 5 0], 2, "last"), [3, 5])