--- ray/src/rt/func.c	1991/06/17 08:28:26	1.16
+++ ray/src/rt/func.c	1991/07/17 10:09:24	1.20
@@ -33,16 +33,15 @@ OBJREC  *m;
 register RAY  *r;
 XF  *bx;
 {
-	extern double  l_arg();
+	extern double  l_arg(), l_erf(), l_erfc();
 	extern long  eclock;
 	static char  *initfile = "rayinit.cal";
 	static long  lastrno = -1;
 					/* check to see if already set */
 	if (m == fobj && r->rno == lastrno)
-		return;
+		return(0);
 					/* initialize if first call */
 	if (initfile != NULL) {
-		loadfunc(initfile);
 		scompile("Dx=$1;Dy=$2;Dz=$3;", NULL, 0);
 		scompile("Nx=$4;Ny=$5;Nz=$6;", NULL, 0);
 		scompile("Px=$7;Py=$8;Pz=$9;", NULL, 0);
@@ -52,7 +51,10 @@ XF  *bx;
 		scompile("Jx=$19;Jy=$20;Jz=$21;", NULL, 0);
 		scompile("Kx=$22;Ky=$23;Kz=$24;", NULL, 0);
 		funset("arg", 1, '=', l_arg);
+		funset("erf", 1, ':', l_erf);
+		funset("erfc", 1, ':', l_erfc);
 		setnoisefuncs();
+		loadfunc(initfile);
 		initfile = NULL;
 	}
 	fobj = m;
@@ -67,6 +69,7 @@ XF  *bx;
 		copystruct(&funcxf, bx);
 	lastrno = r->rno;
 	eclock++;		/* notify expression evaluator */
+	return(1);
 }
 
 
@@ -96,8 +99,7 @@ RAY  *r;
 		}
 		m->os = (char *)mxf;
 	}
-	setmap(m, r, mxf);
-	return;
+	return(setmap(m, r, mxf));
 memerr:
 	error(SYSTEM, "out of memory in setfunc");
 }
@@ -137,6 +139,24 @@ l_arg()				/* return nth real argument */
 
 
 double
+l_erf()				/* error function */
+{
+	extern double  erf();
+
+	return(erf(argument(1)));
+}
+
+
+double
+l_erfc()			/* cumulative error function */
+{
+	extern double  erfc();
+
+	return(erfc(argument(1)));
+}
+
+
+double
 chanvalue(n)			/* return channel n to calcomp */
 register int  n;
 {
@@ -175,8 +195,10 @@ register int  n;
 		return(sum * funcxf.sca);
 
 	}
-	if (n == 10)			/* dot product */
-		return(fray->rod);
+	if (n == 10)			/* dot product (range [-1,1]) */
+		return(	fray->rod <= -1.0 ? -1.0 :
+			fray->rod >= 1.0 ? 1.0 :
+			fray->rod );
 
 	if (n == 11)			/* scale */
 		return(funcxf.sca);