Merge pull request #42 from MisaOgura/2-26_gradient-descent

fix: gradient descent

Author: abhiojha8

intro-neural-networks/gradient-descent/GradientDescent.ipynb

@@ -141,8 +141,6 @@
     "    for e in range(epochs):\n",
     "        del_w = np.zeros(weights.shape)\n",
     "        for x, y in zip(features, targets):\n",
-    "            output = output_formula(x, weights, bias)\n",
-    "            error = error_formula(y, output)\n",
     "            weights, bias = update_weights(x, y, weights, bias, learnrate)\n",
     "        \n",
     "        # Printing out the log-loss error on the training set\n",
@@ -156,7 +154,11 @@
     "            else:\n",
     "                print(\"Train loss: \", loss)\n",
     "            last_loss = loss\n",
+    "            \n",
+    "            # Converting the output (float) to boolean as it is a binary classification\n",
+    "            # e.g. 0.95 --> True (= 1), 0.31 --> False (= 0)\n",
     "            predictions = out > 0.5\n",
+    "            \n",
     "            accuracy = np.mean(predictions == targets)\n",
     "            print(\"Accuracy: \", accuracy)\n",
     "        if graph_lines and e % (epochs / 100) == 0:\n",