title: rendering | (vertical line)as a character in mathjax
body: <p>I'm writing a github jekyll blog and I want to render the char |.I installed mathjax on the blog.</p>
  <p>I can't render the character &quot;|&quot; in mathjax.</p>
  <p>Here is some of my attempts:</p>
  <p><code>&amp;#126</code>,<code>&amp;#7C</code>,a plain <code>|</code> and <code>\|</code>,<code>\left |</code></p>
  <p>None of these attempts succeded.</p>
  <p>The first to the fourth all rendered to be a chart.</p>
  <p>Can anyone help me?</p>