|
| 1 | +{ |
| 2 | + "cells": [ |
| 3 | + { |
| 4 | + "cell_type": "markdown", |
| 5 | + "metadata": {}, |
| 6 | + "source": [ |
| 7 | + "## No Hidden layers" |
| 8 | + ] |
| 9 | + }, |
| 10 | + { |
| 11 | + "cell_type": "code", |
| 12 | + "execution_count": 2, |
| 13 | + "metadata": {}, |
| 14 | + "outputs": [], |
| 15 | + "source": [ |
| 16 | + "import numpy as np" |
| 17 | + ] |
| 18 | + }, |
| 19 | + { |
| 20 | + "cell_type": "code", |
| 21 | + "execution_count": 63, |
| 22 | + "metadata": {}, |
| 23 | + "outputs": [ |
| 24 | + { |
| 25 | + "data": { |
| 26 | + "text/plain": [ |
| 27 | + "((4, 2), (4, 1))" |
| 28 | + ] |
| 29 | + }, |
| 30 | + "execution_count": 63, |
| 31 | + "metadata": {}, |
| 32 | + "output_type": "execute_result" |
| 33 | + } |
| 34 | + ], |
| 35 | + "source": [ |
| 36 | + "X = np.array([[0,0],[0,1],[1,0],[1,1]])\n", |
| 37 | + "Y = np.array([[0,0,0,1]]).T\n", |
| 38 | + "X.shape,Y.shape" |
| 39 | + ] |
| 40 | + }, |
| 41 | + { |
| 42 | + "cell_type": "code", |
| 43 | + "execution_count": 7, |
| 44 | + "metadata": {}, |
| 45 | + "outputs": [], |
| 46 | + "source": [ |
| 47 | + "def sig(z):\n", |
| 48 | + " return 1/(1+np.exp(-z))" |
| 49 | + ] |
| 50 | + }, |
| 51 | + { |
| 52 | + "cell_type": "code", |
| 53 | + "execution_count": 17, |
| 54 | + "metadata": {}, |
| 55 | + "outputs": [], |
| 56 | + "source": [ |
| 57 | + "def derivativeSig(z):\n", |
| 58 | + " return sig(z)*(1-sig(z))" |
| 59 | + ] |
| 60 | + }, |
| 61 | + { |
| 62 | + "cell_type": "code", |
| 63 | + "execution_count": 42, |
| 64 | + "metadata": {}, |
| 65 | + "outputs": [ |
| 66 | + { |
| 67 | + "data": { |
| 68 | + "text/plain": [ |
| 69 | + "(array([[ 0.19225879],\n", |
| 70 | + " [-0.68617919]]), array([-0.94748922]))" |
| 71 | + ] |
| 72 | + }, |
| 73 | + "execution_count": 42, |
| 74 | + "metadata": {}, |
| 75 | + "output_type": "execute_result" |
| 76 | + } |
| 77 | + ], |
| 78 | + "source": [ |
| 79 | + "#no hidden layer\n", |
| 80 | + "# weights = 2 * np.random.random((2,1)) - 1\n", |
| 81 | + "# bais = 2 * np.random.random(1) - 1\n", |
| 82 | + "# lr = 0.01\n", |
| 83 | + "# weights,bais" |
| 84 | + ] |
| 85 | + }, |
| 86 | + { |
| 87 | + "cell_type": "code", |
| 88 | + "execution_count": 72, |
| 89 | + "metadata": {}, |
| 90 | + "outputs": [ |
| 91 | + { |
| 92 | + "data": { |
| 93 | + "text/plain": [ |
| 94 | + "(array([[ 0.83508785],\n", |
| 95 | + " [-0.48865845]]), array([-0.34629789]))" |
| 96 | + ] |
| 97 | + }, |
| 98 | + "execution_count": 72, |
| 99 | + "metadata": {}, |
| 100 | + "output_type": "execute_result" |
| 101 | + } |
| 102 | + ], |
| 103 | + "source": [ |
| 104 | + "weights = 2* np.random.random((2, 1)) - 1\n", |
| 105 | + "bias = 2 * np.random.random(1) - 1\n", |
| 106 | + "lr = 0.1\n", |
| 107 | + "weights, bias" |
| 108 | + ] |
| 109 | + }, |
| 110 | + { |
| 111 | + "cell_type": "code", |
| 112 | + "execution_count": 78, |
| 113 | + "metadata": {}, |
| 114 | + "outputs": [ |
| 115 | + { |
| 116 | + "data": { |
| 117 | + "text/plain": [ |
| 118 | + "(array([[6.55847355],\n", |
| 119 | + " [6.55847355]]), array([-10.68602841]), array([[2.28616145e-05],\n", |
| 120 | + " [1.58664489e-02],\n", |
| 121 | + " [1.58664489e-02],\n", |
| 122 | + " [9.19154826e-01]]))" |
| 123 | + ] |
| 124 | + }, |
| 125 | + "execution_count": 78, |
| 126 | + "metadata": {}, |
| 127 | + "output_type": "execute_result" |
| 128 | + } |
| 129 | + ], |
| 130 | + "source": [ |
| 131 | + "#no hidden layer\n", |
| 132 | + "for iter in range(10000):\n", |
| 133 | + " output0 = X\n", |
| 134 | + " output = sig(np.dot(output0,weights)+bias)\n", |
| 135 | + "\n", |
| 136 | + "\n", |
| 137 | + " first_term = output-Y\n", |
| 138 | + " input_for_the_last_layer = np.dot(output0,weights)+bais\n", |
| 139 | + " second_term = DerivativeSig(input_for_the_last_layer)\n", |
| 140 | + " first_two = first_term * second_term\n", |
| 141 | + " \n", |
| 142 | + " first_two.shape\n", |
| 143 | + " changes = np.array([[0.0],[0.0]])\n", |
| 144 | + "\n", |
| 145 | + " for i in range(2):\n", |
| 146 | + " for j in range(4):\n", |
| 147 | + " changes[i][0] += first_two[j][0] * output0[j][i]\n", |
| 148 | + " weights = weights- lr*changes\n", |
| 149 | + " bais_change = 0.0\n", |
| 150 | + " for j in range(4):\n", |
| 151 | + " bais_change += first_two[j][0] *1\n", |
| 152 | + " bias = bias - lr*bais_change\n", |
| 153 | + "\n", |
| 154 | + "output = sig(np.dot(X,weights)+bias)\n", |
| 155 | + "weights,bias,output" |
| 156 | + ] |
| 157 | + }, |
| 158 | + { |
| 159 | + "cell_type": "code", |
| 160 | + "execution_count": 79, |
| 161 | + "metadata": {}, |
| 162 | + "outputs": [ |
| 163 | + { |
| 164 | + "data": { |
| 165 | + "text/plain": [ |
| 166 | + "(array([[6.50448825],\n", |
| 167 | + " [6.50448825]]), array([-10.79883995]), array([[2.04227644e-05],\n", |
| 168 | + " [1.34617243e-02],\n", |
| 169 | + " [1.34617243e-02],\n", |
| 170 | + " [9.01156090e-01]]))" |
| 171 | + ] |
| 172 | + }, |
| 173 | + "execution_count": 79, |
| 174 | + "metadata": {}, |
| 175 | + "output_type": "execute_result" |
| 176 | + } |
| 177 | + ], |
| 178 | + "source": [ |
| 179 | + "#no hidden layer\n", |
| 180 | + "for iter in range(10000):\n", |
| 181 | + " output0 = X\n", |
| 182 | + " output = sig(np.dot(output0,weights)+bias)\n", |
| 183 | + "\n", |
| 184 | + "\n", |
| 185 | + " first_term = output-Y\n", |
| 186 | + " input_for_the_last_layer = np.dot(output0,weights)+bais\n", |
| 187 | + " second_term = DerivativeSig(input_for_the_last_layer)\n", |
| 188 | + " first_two = first_term * second_term\n", |
| 189 | + " \n", |
| 190 | + " first_two.shape\n", |
| 191 | + " changes = np.dot(output0.T,first_two)\n", |
| 192 | + "\n", |
| 193 | + " weights = weights- lr*changes\n", |
| 194 | + " bais_change = np.sum(first_two)\n", |
| 195 | + " bias = bias - lr*bais_change\n", |
| 196 | + "\n", |
| 197 | + "output = sig(np.dot(X,weights)+bias)\n", |
| 198 | + "weights,bias,output" |
| 199 | + ] |
| 200 | + }, |
| 201 | + { |
| 202 | + "cell_type": "markdown", |
| 203 | + "metadata": {}, |
| 204 | + "source": [ |
| 205 | + "## Hidden Layer Neural Network (XOR)" |
| 206 | + ] |
| 207 | + }, |
| 208 | + { |
| 209 | + "cell_type": "code", |
| 210 | + "execution_count": 3, |
| 211 | + "metadata": {}, |
| 212 | + "outputs": [ |
| 213 | + { |
| 214 | + "data": { |
| 215 | + "text/plain": [ |
| 216 | + "((4, 2), (4, 1))" |
| 217 | + ] |
| 218 | + }, |
| 219 | + "execution_count": 3, |
| 220 | + "metadata": {}, |
| 221 | + "output_type": "execute_result" |
| 222 | + } |
| 223 | + ], |
| 224 | + "source": [ |
| 225 | + "Xh = np.array([[0,0],[0,1],[1,0],[1,1]])\n", |
| 226 | + "Yh = np.array([[0,1,1,0]]).T\n", |
| 227 | + "Xh.shape,Yh.shape" |
| 228 | + ] |
| 229 | + }, |
| 230 | + { |
| 231 | + "cell_type": "code", |
| 232 | + "execution_count": 4, |
| 233 | + "metadata": {}, |
| 234 | + "outputs": [], |
| 235 | + "source": [ |
| 236 | + "wh = 2*np.random.random((2,2))-1\n", |
| 237 | + "bh = 2*np.random.random((1,2))-1\n", |
| 238 | + "wo = 2*np.random.random((2,1))-1\n", |
| 239 | + "bo = 2*np.random.random((1,1)) -1\n", |
| 240 | + "lr = 0.1" |
| 241 | + ] |
| 242 | + }, |
| 243 | + { |
| 244 | + "cell_type": "code", |
| 245 | + "execution_count": 20, |
| 246 | + "metadata": {}, |
| 247 | + "outputs": [ |
| 248 | + { |
| 249 | + "data": { |
| 250 | + "text/plain": [ |
| 251 | + "(array([[0.04218936],\n", |
| 252 | + " [0.95282516],\n", |
| 253 | + " [0.95996342],\n", |
| 254 | + " [0.03735394]]), array([[ 4.91616033, 5.62227738],\n", |
| 255 | + " [-5.14461895, -5.55010192]]), array([[-2.67450006, 2.85794844]]), array([[ 7.98928045],\n", |
| 256 | + " [-7.5259943 ]]), array([[3.47979419]]))" |
| 257 | + ] |
| 258 | + }, |
| 259 | + "execution_count": 20, |
| 260 | + "metadata": {}, |
| 261 | + "output_type": "execute_result" |
| 262 | + } |
| 263 | + ], |
| 264 | + "source": [ |
| 265 | + "#forward propagation\n", |
| 266 | + "for iter in range(10000):\n", |
| 267 | + " output0 =Xh\n", |
| 268 | + " inputHidden = np.dot(output0,wh)+bh\n", |
| 269 | + " outputHidden = sig(inputHidden)\n", |
| 270 | + " inputforOutputLayer = np.dot(outputHidden,wo)+ bo \n", |
| 271 | + " output = sig(inputforOutputLayer)\n", |
| 272 | + " output\n", |
| 273 | + "\n", |
| 274 | + " first_term_for_output_layer = output-Yh\n", |
| 275 | + " second_term_output_layer = derivativeSig(inputforOutputLayer)\n", |
| 276 | + " first_two_term_output_layer = first_term_for_output_layer*second_term_output_layer\n", |
| 277 | + " first_term_hidden_layer = np.dot(first_two_term_output_layer,wo.T)\n", |
| 278 | + " second_term_hidden_layer = derivativeSig(inputHidden)\n", |
| 279 | + " first_two_hidden_layer = first_term_hidden_layer*second_term_hidden_layer\n", |
| 280 | + "\n", |
| 281 | + " changes_output = np.dot(outputHidden.T,first_two_term_output_layer)\n", |
| 282 | + " changes_output_bias = np.sum(first_two_term_output_layer,axis=0,keepdims=True)\n", |
| 283 | + "\n", |
| 284 | + " changes_hidden = np.dot(output0.T,first_two_hidden_layer)\n", |
| 285 | + " changes_hidden_bias = np.sum(first_two_hidden_layer,axis=0,keepdims=True)\n", |
| 286 | + "\n", |
| 287 | + " wo = wo-lr*changes_output\n", |
| 288 | + " bo = bo-lr*changes_output_bias\n", |
| 289 | + "\n", |
| 290 | + " wh = wh - lr*changes_hidden\n", |
| 291 | + " bh = bh - lr*changes_hidden_bias\n", |
| 292 | + "output0 =Xh\n", |
| 293 | + "inputHidden = np.dot(output0,wh)+bh\n", |
| 294 | + "outputHidden = sig(inputHidden)\n", |
| 295 | + "inputforOutputLayer = np.dot(outputHidden,wo)+ bo \n", |
| 296 | + "output = sig(inputforOutputLayer)\n", |
| 297 | + "output,wh,bh,wo,bo" |
| 298 | + ] |
| 299 | + }, |
| 300 | + { |
| 301 | + "cell_type": "code", |
| 302 | + "execution_count": null, |
| 303 | + "metadata": {}, |
| 304 | + "outputs": [], |
| 305 | + "source": [] |
| 306 | + } |
| 307 | + ], |
| 308 | + "metadata": { |
| 309 | + "kernelspec": { |
| 310 | + "display_name": "Python 3", |
| 311 | + "language": "python", |
| 312 | + "name": "python3" |
| 313 | + }, |
| 314 | + "language_info": { |
| 315 | + "codemirror_mode": { |
| 316 | + "name": "ipython", |
| 317 | + "version": 3 |
| 318 | + }, |
| 319 | + "file_extension": ".py", |
| 320 | + "mimetype": "text/x-python", |
| 321 | + "name": "python", |
| 322 | + "nbconvert_exporter": "python", |
| 323 | + "pygments_lexer": "ipython3", |
| 324 | + "version": "3.6.4" |
| 325 | + } |
| 326 | + }, |
| 327 | + "nbformat": 4, |
| 328 | + "nbformat_minor": 2 |
| 329 | +} |
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