Array find polyfill for IE support.

index.html

@@ -317,6 +317,30 @@
 
     (function(){
 
+        // array prorotype find polyfill
+        if (!Array.prototype.find) {
+          Array.prototype.find = function(predicate) {
+            if (this == null) {
+              throw new TypeError('Array.prototype.find called on null or undefined');
+            }
+            if (typeof predicate !== 'function') {
+              throw new TypeError('predicate must be a function');
+            }
+            var list = Object(this);
+            var length = list.length >>> 0;
+            var thisArg = arguments[1];
+            var value;
+
+            for (var i = 0; i < length; i++) {
+              value = list[i];
+              if (predicate.call(thisArg, value, i, list)) {
+                return value;
+              }
+            }
+            return undefined;
+          };
+        }
+
         document.onStationChosen = function(node){
             selectedStation = node.getAttribute('value');
             updateView(node.getAttribute('name'));