Added an minNumberOfMeasures option

README.md

@@ -7,7 +7,7 @@ Use this script to detect slow users on your website, so you can improve their n
 
 ```Slowness = Frustration```
 
-**Think UX First!** Remove non-important things from your pages when the user has already been waiting for ages.
+**Think UX First!** Remove non-important things from your interface when the user has already been waiting for ages.
 
 ## Usage
 
@@ -28,6 +28,20 @@ Before the first page is fully loaded, the average will be `null` (and `null` is
 </script>
 ```
 
+## Options
+
+### minNumberOfMeasures (optional)
+
+The `uxFirst` function will return `null` as long as the number of measures is not reached. Default is 1.
+
+```js
+// Wait for 3 measures before using uxFirst
+if (uxFirst(3) < 10000) { ... }
+```
+
+It can help reducing yo-yo effect: the 1st page loads slowly - UXFirst helps accelerating the 2nd page and the average load-time gets under your limit - the 3rd page loads slowly again... The page content could look inconsistent if you use this script to remove a functionnality the user might be looking for.
+
+
 ## Use cases
 
 - Don't load ads for users already having a slow navigation

package.json

@@ -1,7 +1,7 @@
 {
   "name": "UXFirst",
   "description": "Small Javascript that tells you if a visitor is having a bad user experience because your site is slow",
-  "version": "0.1.0",
+  "version": "0.2.0",
   "homepage": "https://github.com/gmetais/UXFirst",
   "author": {
     "name": "Gaël Métais",

uxfirst.js

@@ -65,19 +65,21 @@
     }
 
 
-    global.uxFirst = function() {
-            var localData = readLocalStorage();
-            var sum = 0;
-            var dataLength = localData.length;
-            if(dataLength < 3) {
-                return null;
-            }
+    global.uxFirst = function(minNumberOfMeasures) {
+        var minNumber = minNumberOfMeasures || 1;
+        var localData = readLocalStorage();
+        var dataLength = localData.length;
+        var sum = 0;
+
+        if(dataLength < minNumberOfMeasures) {
+            return null;
+        }
 
-            for (var i=0, max=dataLength ; i<max ; i++) {
-                sum += localData[i].l;
-            }
+        for (var i=0, max=dataLength ; i<max ; i++) {
+            sum += localData[i].l;
+        }
 
-            return Math.round(sum / dataLength) || null;
+        return Math.round(sum / dataLength);
     };
 
 }(this));