title: Plotting resulting fitted curve with scipy
body: <p>According to <a href="https://stackoverflow.com/questions/5884768/skew-normal-distribution-in-scipy">this</a>, what about if I want to overplot the fitted curve over the data points? Should I define the fitting function again?</p>
  <p>Leastsq method has lacking documentation and examples, and I have some troubles in understanding the arguments it needs.</p>
  <p>According to that, if I define:</p>
  <pre><code>def optm(l, x, y):
      return skew(x, l[0], l[1], l[2]) - y
  </code></pre>
  <p>Then, is it correct to fit in the following way:</p>
  <pre><code>out_param = leastsq(optm, v1[:], args = (x_values, y_values), maxfev = 100000, full_output = 1)
  </code></pre>
  <p>(where <code>v1[:]</code> is the vector with the initial guess parameters)?
  And then, again, how can I plot the resulting curve?</p>
  <p>I am still trying to understand so any suggestion is really appreciated.</p>