title: How to parse a symbolic expression in Matlab
body: <p>In Matlab 2016a, Mathworks deprecated the use of the <code>sym</code> function for parsing symbolic expressions:</p>
  
  <pre><code>&gt;&gt; expr = sym('x + 1')
  Warning: Support of strings that are not valid variable names or define a number will be
  removed in a future release. To create symbolic expressions, first create symbolic
  variables and then use operations on them. 
  &gt; In sym&gt;convertExpression (line 1536)
    In sym&gt;convertChar (line 1441)
    In sym&gt;tomupad (line 1198)
    In sym (line 177) 
  
  expr =
  
  x + 1
  </code></pre>
  
  <p>The warning's suggestion is not practical when the symbolic expressions are being read from a file rather than built by hand in code. Is there a function in Matlab to replace this functionality? I would rather not <code>regexprep</code> and <code>eval</code> my way through it.</p>