Merge pull request dibgerge#15 from ncliang/patch-1

Copy/paste bug in ex2

Author: dibgerge

Exercise2/exercise2.ipynb

@@ -817,7 +817,7 @@
     "print('Cost at test theta    : {:.2f}'.format(cost))\n",
     "print('Expected cost (approx): 3.16\\n')\n",
     "\n",
-    "print('Gradient at initial theta (zeros) - first five values only:')\n",
+    "print('Gradient at test theta - first five values only:')\n",
     "print('\\t[{:.4f}, {:.4f}, {:.4f}, {:.4f}, {:.4f}]'.format(*grad[:5]))\n",
     "print('Expected gradients (approx) - first five values only:')\n",
     "print('\\t[0.3460, 0.1614, 0.1948, 0.2269, 0.0922]')"