Corrected the SVM margins

smujjiga · web-flow · commit deb9862641b0 · 2018-12-03T14:27:27.000+05:30
The margins are calculated wrongly.

margin = |c2-c1|/sqrt(1+m^2) =&gt; c2 = margin*sqrt(1+m^2) + c1 = &gt; y_up= m*x+  margin*sqrt(1+m^2) + c1 =&gt; y_up = (m*x+  c1) + margin*sqrt(1+m^2) =&gt; y_up = y + margin*sqrt(1+m^2)
diff --git a/_posts/scikit/svm-margins/SVM Margins.ipynb b/_posts/scikit/svm-margins/SVM Margins.ipynb
@@ -171,8 +171,8 @@
     "    # plot the parallels to the separating hyperplane that pass through the\n",
     "    # support vectors\n",
     "    margin = 1 / np.sqrt(np.sum(clf.coef_ ** 2))\n",
-    "    yy_down = yy + a * margin\n",
-    "    yy_up = yy - a * margin\n",
+    "    yy_down = yy + np.sqrt(1 + a ** 2) * margin\n",
+    "    yy_up = yy - np.sqrt(1 + a ** 2) * margin\n",
     "    \n",
     "    x_min = -4.8\n",
     "    x_max = 4.2\n",
