title: Infinity symbol does not show in Matlab plot
body: <p>I'm trying to include the infinity symbol <code>∞</code> in my axis label (<em>e.g.</em> the expression <code>δ<sub>∞</sub></code>), so I typed <code>\delta_{\infty}</code>. However, I only see the delta symbol <code>δ</code> but the infinity symbol is portrayed as a subscripted black diamond with a question mark inside.</p>
  
  <p>The interpreter is set to Tex and I tried different fonts with other symbols. The greek letters seem to be working but other symbols like <code>\clubsuit</code> (<code>♣</code>) don't. Do I need to make any other changes to the settings?</p>