Index: /branches/eam_branches/ipp-20211108/Ohana/src/opihi/cmd.data/match2d.c
===================================================================
--- /branches/eam_branches/ipp-20211108/Ohana/src/opihi/cmd.data/match2d.c	(revision 41991)
+++ /branches/eam_branches/ipp-20211108/Ohana/src/opihi/cmd.data/match2d.c	(revision 41992)
@@ -140,4 +140,15 @@
   gprint (GP_ERR, "if -index1 or -index2 is not supplied, the vectors are created with names index1 or index2\n");
   gprint (GP_ERR, "use 'reindex' to generate new vectors based on these index vectors\n");
+
+  gprint (GP_ERR, "examples:\n");
+  gprint (GP_ERR, " for 'match2d x1 y1 x2 y2 radius -closest'\n");
+  gprint (GP_ERR, " use 'reindex x2m = x2 using index1 -keep-unmatched'\n");
+  gprint (GP_ERR, "   x2m will have values which correspond to x1 (or NAN if not matched)\n");  
+  gprint (GP_ERR, " \n");  
+  gprint (GP_ERR, " for 'match2d x1 y1 x2 y2 radius'\n");
+  gprint (GP_ERR, " use 'reindex x1m = x1 using index1'\n");
+  gprint (GP_ERR, " use 'reindex x2m = x2 using index2'\n");
+  gprint (GP_ERR, "   x1m will have values which correspond to x2m\n");  
+  gprint (GP_ERR, " \n");  
 
   gprint (GP_ERR, "if -sphere or -sky is supplied, (x1,y1) and (x2,y2) are treaded as (ra,dec) or (long,lat) pairs in degrees\n");
Index: /branches/eam_branches/ipp-20211108/Ohana/src/opihi/cmd.data/reindex.c
===================================================================
--- /branches/eam_branches/ipp-20211108/Ohana/src/opihi/cmd.data/reindex.c	(revision 41991)
+++ /branches/eam_branches/ipp-20211108/Ohana/src/opihi/cmd.data/reindex.c	(revision 41992)
@@ -62,5 +62,5 @@
       if (*vx < 0) {
 	if (KEEP_UNMATCH) {
-	  ovec[0].elements.Flt[Npts] = -1;
+	  ovec[0].elements.Int[Npts] = -4096; // XXX use a different or a specified value?
 	  Npts++;
 	}