diff --git a/.gitignore b/.gitignore
index ea8c4bf..d74d08d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,3 @@
+.DS_Store
+
 /target
diff --git a/tests/draw.html b/tests/draw.html
index 48e9f87..e7013e4 100644
--- a/tests/draw.html
+++ b/tests/draw.html
@@ -110,7 +110,8 @@
                 }
 
 
-                console.log()
+                let cap = -0.5 / (22000 * Math.log(min/max));
+                console.log(`Calculated capacitance: ${cap}`);
             }
 
             function GetYForData(val) {