diff --git a/iloc.c b/iloc.c
index 74fd479..b194b27 100644
--- a/iloc.c
+++ b/iloc.c
@@ -7,7 +7,7 @@
 #include <stdlib.h>
 #include <math.h>
 
-#define u 1.2566370621219E-6 // µ - permeability of free space
+#define u 1.2566370621219E-6 // µ - magnetic constant
 
 int main()
 {
diff --git a/tankfreq.c b/tankfreq.c
index 42eec9a..acdbc0b 100644
--- a/tankfreq.c
+++ b/tankfreq.c
@@ -8,8 +8,8 @@ int main (int argc, char **argv)
 {
     if (argc == 3)
     {
-        printf ("%f\n", 1 / (3.14159265358979324 * 2 * sqrt (atof(argv[1]) /
-            1000000 * atof(argv[2]) / 1000000)));
+        printf ("%f\n", 1 / (M_PI * 2 * sqrt(atof(argv[1]) \
+            * atof(argv[2]))) * 1000000);
         return (0);
     }
     else