title: How to implement exponential with fixed point numbers?
body: <p>How can I implement a code in verilog that resolves a exponential equation that has numbers that must be represented as fixed point.</p>
  
  <p>For example I have this equation on C++ and wish to convert to Verilog or VHDL:</p>
  
  <pre><code>double y = 0.1+0.75*(1.0/(1.0+exp((x[i]+40.5)/6.0)));
  </code></pre>
  
  <p>Where 'y' and 'x' must be fixed point numbers. And 'x' is a vector also.</p>
  
  <p>I looked up for modules and libraries that has fixed point but none of them have exponentials.</p>