title: Decision boundary calculation in SVM
body: <p>I am unable to understand how decision boundary is calculated once we get the coefficients of the model.</p>
  
  <p>Here is the link that I am referring: <a href="http://scikit-learn.org/stable/auto_examples/svm/plot_svm_margin.html" rel="nofollow noreferrer">http://scikit-learn.org/stable/auto_examples/svm/plot_svm_margin.html</a></p>
  
  <p>Here is the code</p>
  
  <pre><code># get the separating hyperplane
  w = clf.coef_[0]
  a = -w[0] / w[1]
  xx = np.linspace(-5, 5)
  yy = a * xx - (clf.intercept_[0]) / w[1]
  </code></pre>
  
  <p>I didn't understand <code>a = -w[0] / w[1]</code> this line.</p>
  
  <p>Why we are dividing one coefficient with another?</p>