Infinity symbol does not show in Matlab plot

Question

I'm trying to include the infinity symbol ∞ in my axis label (e.g. the expression δ∞), so I typed \delta_{\infty}. However, I only see the delta symbol δ but the infinity symbol is portrayed as a subscripted black diamond with a question mark inside.

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 \clubsuit (♣) don't. Do I need to make any other changes to the settings?

Answer 1

From this I make up that you should use LaTeX as the interpreter, rather than TeX:

http://www.mathworks.com/matlabcentral/answers/21984

Answer 2

If you're still looking for answer, it works for you: \delta_\infty = δ∞