--- ray/src/px/pcompos.c	1992/09/21 12:13:57	2.15
+++ ray/src/px/pcompos.c	1993/06/04 14:47:01	2.16
@@ -12,6 +12,8 @@ static char SCCSid[] = "$SunId$ LBL";
 
 #include  <stdio.h>
 
+#include  <math.h>
+
 #ifdef MSDOS
 #include  <fcntl.h>
 #endif