add clarity to solution code

Author: cezannec

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

@@ -200,29 +200,11 @@
    "source": [
     "train(X, y, epochs, learnrate, True)"
    ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "metadata": {
-    "collapsed": true
-   },
-   "outputs": [],
-   "source": []
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "metadata": {
-    "collapsed": true
-   },
-   "outputs": [],
-   "source": []
   }
  ],
  "metadata": {
   "kernelspec": {
-   "display_name": "Python 3",
+   "display_name": "Python [default]",
    "language": "python",
    "name": "python3"
   },
@@ -236,7 +218,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.6.1"
+   "version": "3.6.4"
   }
  },
  "nbformat": 4,

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

@@ -27,16 +27,16 @@
     "\n",
     "def update_weights(x, y, weights, bias, learnrate):\n",
     "    output = output_formula(x, weights, bias)\n",
-    "    d_error = -(y - output)\n",
-    "    weights -= learnrate * d_error * x\n",
-    "    bias -= learnrate * d_error\n",
+    "    d_error = y - output\n",
+    "    weights += learnrate * d_error * x\n",
+    "    bias += learnrate * d_error\n",
     "    return weights, bias"
    ]
   }
  ],
  "metadata": {
   "kernelspec": {
-   "display_name": "Python 3",
+   "display_name": "Python [default]",
    "language": "python",
    "name": "python3"
   },
@@ -50,7 +50,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.6.1"
+   "version": "3.6.4"
   }
  },
  "nbformat": 4,