Index: trunk/Ohana/src/opihi/cmd.astro/precess.c
===================================================================
--- trunk/Ohana/src/opihi/cmd.astro/precess.c	(revision 7917)
+++ trunk/Ohana/src/opihi/cmd.astro/precess.c	(revision 20936)
@@ -90,7 +90,14 @@
   }
   
-  for (i = 0; i < xvec[0].Nelements; i++) {
-    A = xvec[0].elements[i];
-    D = yvec[0].elements[i];
+  // cast xvec or yvec to FLT if it is type INT
+  CastVector (xvec, OPIHI_FLT);
+  CastVector (yvec, OPIHI_FLT);
+
+  opihi_flt *Av = xvec[0].elements.Flt;
+  opihi_flt *Dv = yvec[0].elements.Flt;
+
+  for (i = 0; i < xvec[0].Nelements; i++, Av, Dv) {
+    A = *Av;
+    D = *Dv;
     SD =  cos(RAD_DEG*A + zeta)*sin(theta)*cos(RAD_DEG*D) + cos(theta)*sin(RAD_DEG*D);
     CD = sqrt (1 - SD*SD);
@@ -101,9 +108,8 @@
     RA  = DEG_RAD*atan2(SA, CA) + z;
 
-    if (RA < 0)
-      RA += 360;
+    if (RA < 0) RA += 360;
     
-    xvec[0].elements[i] = RA;
-    yvec[0].elements[i] = DEC; 
+    *Av = RA;
+    *Dv = DEC; 
   }