title: Vue.js counting json value
body: <p>I have this Json</p>
  
  <pre><code>all_subjects: [
  {
  id: 1,
  subject_code: "COMP101",
  description: "Knowledge Work Software &amp; Presentation ",
  name: "",
  grade: [
  {
  id: 103,
  subject_id: "1",
  user_id: "17",
  grade: "F",
  reviewed: "0"
  },
  {
  id: 104,
  subject_id: "1",
  user_id: "16",
  grade: "F",
  reviewed: "0"
  }
  ]
  },
  </code></pre>
  
  <blockquote>
    <p>my view</p>
  </blockquote>
  
  <pre><code> &lt;tbody v-for="subject in subjects"&gt;
          &lt;tr&gt;
            &lt;td&gt;
              &lt;span&gt; @{{ subject.subject_code }}&lt;/span&gt;
            &lt;/td&gt;
            &lt;td&gt;
              &lt;span&gt; @{{ subject.description }} &lt;/span&gt;
            &lt;/td&gt;
            &lt;td&gt;
              &lt;span&gt; @{{ subject.grade.grade-&gt;count() }} &lt;/span&gt;
            &lt;/td&gt;
            &lt;td&gt;&lt;span&gt; &lt;div class="btn btn-crimson btn-inline-block"&gt;&lt;a href="#" data-toggle="modal" data-target="#myModal" class="btn-view-more"&gt;View more info&lt;/a&gt;&lt;/div&gt; &lt;/span&gt;&lt;/td&gt;
          &lt;/tr&gt;       
        &lt;/tbody&gt;
  </code></pre>
  
  <p>how do I count the that is F.
  I received the json value using vue.resource this.$http.get throught API Call.
  I'm trying this @{{ all_subjects.grade.grade->count() }} it doesn't work.
  I wanted to count the subjects failure inside the v-for loop in vue.js what are the ways around this?</p>