Cleaning up tests and printing for demo

tests_ispcpp/varying.ispc

@@ -1,5 +1,5 @@
-floating foo(const uniform int a, floating b) {
-    floating out = b;
+number pow(number b, int a) {
+    number out = b;
     for (int i = 1; i<a; i++) {
         out *= b;
     }
@@ -7,8 +7,8 @@ floating foo(const uniform int a, floating b) {
     return out;
 }
 
-export void square(uniform int N, uniform floating b[], uniform double out[]) {
+export void square(uniform int N, uniform number b[], uniform number out[]) {
     foreach (i = 0 ... N) {
-        out[i] = foo(2, b[i]);
+        out[i] = pow(b[i], 2);
     }
 }