Fixed the segfault in last failing cell in the MMD notebook

- Present state of the notebook at this commit:
  https://gist.github.com/lambday/2fb59fbf828e8ad38bff0f2c095c1edc

doc/ipython-notebooks/statistical_testing/mmd_two_sample_testing.ipynb

@@ -921,16 +921,14 @@
    "outputs": [],
    "source": [
     "# mmd instance using streaming features\n",
-    "block_size=100\n",
-    "m=1000\n",
     "mmd=sg.LinearTimeMMD(gen_p, gen_q)\n",
     "mmd.set_num_samples_p(m)\n",
     "mmd.set_num_samples_q(m)\n",
     "mmd.set_num_blocks_per_burst(block_size)\n",
     "\n",
-    "sigmas=[2**x for x in linspace(-5, 5, 10)]\n",
+    "sigmas=[2**x for x in np.linspace(-5, 5, 11)]\n",
     "print \"Choosing kernel width from\", [\"{0:.2f}\".format(sigma) for sigma in sigmas]\n",
-    "combined=sg.CombinedKernel()\n",
+    "\n",
     "for i in range(len(sigmas)):\n",
     "    mmd.add_kernel(sg.GaussianKernel(10, sigmas[i]))\n",
     "\n",
@@ -940,12 +938,10 @@
     "# must be set true for kernel selection\n",
     "mmd.set_train_test_mode(True)\n",
     "\n",
-    "# use 50% of the data to perform training (selecting the kernel)\n",
-    "mmd.set_train_test_ratio(1)\n",
-    "\n",
     "# select best kernel\n",
-    "best_kernel=mmd.select_kernel()\n",
+    "mmd.select_kernel()\n",
     "\n",
+    "best_kernel=mmd.get_kernel()\n",
     "best_kernel=sg.GaussianKernel.obtain_from_generic(best_kernel)\n",
     "print \"Best single kernel has bandwidth %.2f\" % best_kernel.get_width()"
    ]
@@ -989,6 +985,7 @@
     "m=5000\n",
     "mmd.set_num_samples_p(m)\n",
     "mmd.set_num_samples_q(m)\n",
+    "mmd.set_train_test_mode(False)\n",
     "num_samples=500\n",
     "\n",
     "# sample null and alternative distribution, implicitly generate new data for that\n",