Add mode filter

Author: DavidePastore

README.md

@@ -71,6 +71,7 @@
   - [shortFmt](#shortfmt)
   - [byteFmt](#bytefmt)
   - [kbFmt](#kbfmt)
+  - [mode] (#mode)
 - [Boolean](#boolean)
   - [isNull](#isnull)
   - [isDefined](#isdefined)
@@ -1222,6 +1223,14 @@ Converts kilobytes into formatted display<br/>
 1 MB
 1.00126 GB
 
+```
+###mode
+Calculates the mode value from all values within an array<br/>
+**Usage:** ```array | mode```
+```html
+{{ [12,7,5,7] | mode }}
+<!--result
+7
 ```
 #Boolean
 >Used for boolean expression in chaining filters

src/_filter/math/mode.js

@@ -0,0 +1,36 @@
+/**
+ * @ngdoc filter
+ * @name mode
+ * @kind function
+ *
+ * @description
+ * Math.mode will get an array and return the mode value.
+ */
+angular.module('a8m.math.mode', ['a8m.math'])
+  .filter('mode', ['$math', function ($math) {
+    return function (input) {
+
+      if(!isArray(input)) {
+        return input;
+      }
+      
+      var modeMap = {};
+      var mode = input[0];
+      var maxCount = 1;
+      for (var i = 0; i < input.length; i++) {
+          var val = input[i];
+          if(isDefined(modeMap[val])){
+              modeMap[val]++;
+          } else {
+              modeMap[val] = 1;
+          }
+          
+          if(modeMap[val] > maxCount){
+    		  mode = val;
+    		  maxCount = modeMap[val];
+    	  }
+      }
+
+      return mode;
+    };
+  }]);

src/filters.js

@@ -66,6 +66,7 @@ angular.module('angular.filter', [
   'a8m.math.byteFmt',
   'a8m.math.kbFmt',
   'a8m.math.shortFmt',
+  'a8m.math.mode',
 
   'a8m.angular',
   'a8m.conditions',

test/spec/filter/math/mode.js

@@ -0,0 +1,27 @@
+'use strict';
+
+describe('modeFilter', function () {
+
+  var filter;
+
+  beforeEach(module('a8m.math.mode'));
+
+  beforeEach(inject(function ($filter) {
+    filter = $filter('mode');
+  }));
+
+  it('should get an array of numbers and return the mode', function() {
+    expect(filter([1,2,3,4,5])).toEqual(1);
+    expect(filter([2,0,2,2,2])).toEqual(2);
+    expect(filter([1,2.32,2.32,7,5])).toEqual(2.32);
+    expect(filter([4])).toEqual(4);
+  });
+
+
+  it('should get an !array and return it as-is', function() {
+    expect(filter('string')).toEqual('string');
+    expect(filter({})).toEqual({});
+    expect(filter(!0)).toBeTruthy();
+  });
+
+});