title: Adding Gaussian noise
body: <p>I have a <code>.arff</code> file which contains a list of float numbers. I need to add to every number a gaussian noise, which in MATLAB would be:</p>
  
  <pre><code>m = m+k*randn(size(m)
  </code></pre>
  
  <p>where <code>m</code> is one of the numbers in the list and <code>k</code> is a standard deviation and has value <code>0.1</code>. What is the <code>C++</code> equivalent to <code>randn()</code>?</p>
  
  <p>Could you please provide an example?</p>