title: How to use the order and group by in ng-repeat with data format
body: <p>I have a json as</p>
  
  <pre class="lang-js prettyprint-override"><code>[{
    "type" : "visible_product",
    "description" : "asdjkjasd asdak",
    "launch_date" : "2015-12-03T10:42:34.972Z"
   }, {
    "type" : "non_visible_product",
    "description" : "askjd asdkasd askdjkasd",
    "launch_date" : "2015-12-03T10:44:34.972Z"
   }, {
    "type" : "durable_product",
    "description" : "asdjkjasd asdak",
    "launch_date" : "2015-12-04T10:41:34.972Z"
   }, {
    "type" : "non_durable_product",
    "description" : "asdjkjasd asdak",
    "launch_date" : "2015-12-04T10:44:34.972Z"
   }, {
    "type" : "visible_product",
    "description" : "asdjkjasd asdak",
    "launch_date" : "2015-12-04T10:44:30.972Z"
   }, {
    "type" : "visible_product",
    "description" : "asdjkjasd asdak",
    "launch_date" : "2015-12-06T10:44:34.972Z"
   }]
  </code></pre>
  
  <p>I am displaying the data as list in descending sorting order </p>
  
  <pre class="lang-html prettyprint-override"><code>&lt;md-list-item class="md-2-line my-list" 
                ng-repeat="item in my_json_data | orderBy:'-launch_date'" 
                ng-class="{launch_sel: $index == selected}"&gt;
    &lt;div class="md-list-item-text" layout="column" &gt;
      &lt;a class="md-accent url-no-decoration"  href=""
         ng-click="myfunction(item.type, $index)" style="cursor:pointer"&gt;
        &lt;h3&gt; {{ item.type }} &lt;/h3&gt;
        &lt;p&gt; {{ item.description}} &lt;/p&gt;
        &lt;p&gt;{{ item.launch_date | date:'dd-MMM-yy HH:mm'}}&lt;/p&gt;
      &lt;/a&gt;
    &lt;/div&gt;
  &lt;/md-list-item&gt;
  </code></pre>
  
  <p>When I tried to display the data based on grouping on date its not working.
  List should be sorted and grouped as 2 data for day 6, next there should be no day 5 as json has no data in the list,
  then day 4 and then day 3.</p>
  
  <pre class="lang-html prettyprint-override"><code>&lt;div ng-repeat="(key, value) in my_json_data | orderBy:'-launch_date'"&gt;
    &lt;h3&gt;Group name: {{ key }}&lt;/h3&gt;
    &lt;md-list-item class="md-2-line my-list" 
                  ng-repeat="item in my_json_data | orderBy:'-launch_date'" 
                  ng-class="{launch_sel: $index == selected}"&gt;
      &lt;div class="md-list-item-text" layout="column" &gt;
        &lt;a class="md-accent url-no-decoration"  href=""
           ng-click="myfunction(item.type, $index)" style="cursor:pointer"&gt;
          &lt;h3&gt; {{ item.type }} &lt;/h3&gt;
          &lt;p&gt; {{ item.description}} &lt;/p&gt;
          &lt;p&gt;{{ item.launch_date | date:'dd-MMM-yy HH:mm'}}&lt;/p&gt;
        &lt;/a&gt;
      &lt;/div&gt;
    &lt;/md-list-item&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>How to display data as </p>
  
  <pre><code>Dec 6 
     //data 1
  Dec 4
     //data 2
     //data 3
     //data 4
  Dec 3
     //data 5
     //data 6
  </code></pre>