|
| 1 | +{ |
| 2 | + "cells": [ |
| 3 | + { |
| 4 | + "cell_type": "markdown", |
| 5 | + "id": "b314e777-7ffb-4e62-b4c5-ce8a785c5181", |
| 6 | + "metadata": {}, |
| 7 | + "source": [ |
| 8 | + "# End-to-End Tutorial: Training a Neural Network with Keras and Xbatcher\n", |
| 9 | + "\n", |
| 10 | + "## Import Required Libraries" |
| 11 | + ] |
| 12 | + }, |
| 13 | + { |
| 14 | + "cell_type": "code", |
| 15 | + "execution_count": null, |
| 16 | + "id": "5d912ff0-d808-4704-8dea-b9e1b5a53bf1", |
| 17 | + "metadata": {}, |
| 18 | + "outputs": [], |
| 19 | + "source": [ |
| 20 | + "import matplotlib.pyplot as plt\n", |
| 21 | + "import tensorflow as tf\n", |
| 22 | + "import xarray as xr\n", |
| 23 | + "from keras import layers, models, optimizers\n", |
| 24 | + "\n", |
| 25 | + "import xbatcher as xb\n", |
| 26 | + "import xbatcher.loaders.keras" |
| 27 | + ] |
| 28 | + }, |
| 29 | + { |
| 30 | + "cell_type": "code", |
| 31 | + "execution_count": null, |
| 32 | + "id": "7fb892c1-50fd-48c8-8567-b150946b53c9", |
| 33 | + "metadata": {}, |
| 34 | + "outputs": [], |
| 35 | + "source": [ |
| 36 | + "# Open the dataset stored in Zarr format\n", |
| 37 | + "ds = xr.open_dataset(\n", |
| 38 | + " 's3://carbonplan-share/xbatcher/fashion-mnist-train.zarr',\n", |
| 39 | + " engine='zarr',\n", |
| 40 | + " chunks={},\n", |
| 41 | + " backend_kwargs={'storage_options': {'anon': True}},\n", |
| 42 | + ")" |
| 43 | + ] |
| 44 | + }, |
| 45 | + { |
| 46 | + "cell_type": "markdown", |
| 47 | + "id": "c98134fe-581f-412a-93e3-6b07b7706078", |
| 48 | + "metadata": {}, |
| 49 | + "source": [ |
| 50 | + "## Define Batch Generators" |
| 51 | + ] |
| 52 | + }, |
| 53 | + { |
| 54 | + "cell_type": "code", |
| 55 | + "execution_count": null, |
| 56 | + "id": "c680ebd7-0310-4f40-91b5-e7cc1a59e853", |
| 57 | + "metadata": {}, |
| 58 | + "outputs": [], |
| 59 | + "source": [ |
| 60 | + "# Define batch generators for features (X) and labels (y)\n", |
| 61 | + "X_bgen = xb.BatchGenerator(\n", |
| 62 | + " ds['images'],\n", |
| 63 | + " input_dims={'sample': 2000, 'channel': 1, 'height': 28, 'width': 28},\n", |
| 64 | + " preload_batch=False, # Load each batch dynamically\n", |
| 65 | + ")\n", |
| 66 | + "y_bgen = xb.BatchGenerator(\n", |
| 67 | + " ds['labels'], input_dims={'sample': 2000}, preload_batch=False\n", |
| 68 | + ")" |
| 69 | + ] |
| 70 | + }, |
| 71 | + { |
| 72 | + "cell_type": "markdown", |
| 73 | + "id": "91d63180-e3a6-49f7-a8e7-67b8b698b08c", |
| 74 | + "metadata": {}, |
| 75 | + "source": [ |
| 76 | + "## Map Batches to a Keras-Compatible Dataset" |
| 77 | + ] |
| 78 | + }, |
| 79 | + { |
| 80 | + "cell_type": "code", |
| 81 | + "execution_count": null, |
| 82 | + "id": "d1195057-269b-44ba-a3e7-aeedaa4ba8df", |
| 83 | + "metadata": {}, |
| 84 | + "outputs": [], |
| 85 | + "source": [ |
| 86 | + "# Use xbatcher's MapDataset to wrap the generators\n", |
| 87 | + "dataset = xbatcher.loaders.keras.CustomTFDataset(X_bgen, y_bgen)\n", |
| 88 | + "\n", |
| 89 | + "# Create a DataLoader using tf.data.Dataset\n", |
| 90 | + "train_dataloader = tf.data.Dataset.from_generator(\n", |
| 91 | + " lambda: iter(dataset),\n", |
| 92 | + " output_signature=(\n", |
| 93 | + " tf.TensorSpec(shape=(2000, 1, 28, 28), dtype=tf.float32), # Images\n", |
| 94 | + " tf.TensorSpec(shape=(2000,), dtype=tf.int64), # Labels\n", |
| 95 | + " ),\n", |
| 96 | + ").prefetch(3) # Prefetch 3 batches to improve performance" |
| 97 | + ] |
| 98 | + }, |
| 99 | + { |
| 100 | + "cell_type": "code", |
| 101 | + "execution_count": null, |
| 102 | + "id": "1892411c-ca17-4d7f-b76b-5b5decaa78c1", |
| 103 | + "metadata": {}, |
| 104 | + "outputs": [], |
| 105 | + "source": [ |
| 106 | + "## Visualize a Sample Batch" |
| 107 | + ] |
| 108 | + }, |
| 109 | + { |
| 110 | + "cell_type": "code", |
| 111 | + "execution_count": null, |
| 112 | + "id": "133b24bc-e7bc-4734-ad0a-22a848dd204c", |
| 113 | + "metadata": {}, |
| 114 | + "outputs": [], |
| 115 | + "source": [ |
| 116 | + "# Extract a batch from the DataLoader\n", |
| 117 | + "for train_features, train_labels in train_dataloader.take(1):\n", |
| 118 | + " print(f'Feature batch shape: {train_features.shape}')\n", |
| 119 | + " print(f'Labels batch shape: {train_labels.shape}')\n", |
| 120 | + "\n", |
| 121 | + " img = train_features[0].numpy().squeeze() # Extract the first image\n", |
| 122 | + " label = train_labels[0].numpy()\n", |
| 123 | + " plt.imshow(img, cmap='gray')\n", |
| 124 | + " plt.title(f'Label: {label}')\n", |
| 125 | + " plt.show()\n", |
| 126 | + " break" |
| 127 | + ] |
| 128 | + }, |
| 129 | + { |
| 130 | + "cell_type": "markdown", |
| 131 | + "id": "1e5d6a66-1943-47da-be67-9b54d51defed", |
| 132 | + "metadata": {}, |
| 133 | + "source": [ |
| 134 | + "## Build a Simple Neural Network with Keras" |
| 135 | + ] |
| 136 | + }, |
| 137 | + { |
| 138 | + "cell_type": "code", |
| 139 | + "execution_count": null, |
| 140 | + "id": "8b0490e5-7ccc-47fe-90ec-d41a81c4eb20", |
| 141 | + "metadata": {}, |
| 142 | + "outputs": [], |
| 143 | + "source": [ |
| 144 | + "# Define a simple feedforward neural network\n", |
| 145 | + "model = models.Sequential(\n", |
| 146 | + " [\n", |
| 147 | + " layers.Flatten(input_shape=(1, 28, 28)), # Flatten input images\n", |
| 148 | + " layers.Dense(128, activation='relu'), # Fully connected layer with 128 units\n", |
| 149 | + " layers.Dense(10, activation='softmax'), # Output layer for 10 classes\n", |
| 150 | + " ]\n", |
| 151 | + ")\n", |
| 152 | + "\n", |
| 153 | + "# Compile the model\n", |
| 154 | + "model.compile(\n", |
| 155 | + " optimizer=optimizers.Adam(learning_rate=0.001),\n", |
| 156 | + " loss='sparse_categorical_crossentropy',\n", |
| 157 | + " metrics=['accuracy'],\n", |
| 158 | + ")\n", |
| 159 | + "\n", |
| 160 | + "# Display model summary\n", |
| 161 | + "model.summary()" |
| 162 | + ] |
| 163 | + }, |
| 164 | + { |
| 165 | + "cell_type": "markdown", |
| 166 | + "id": "838df9c6-0753-4120-a0e0-dcc1480416b4", |
| 167 | + "metadata": {}, |
| 168 | + "source": [ |
| 169 | + "## Train the Model " |
| 170 | + ] |
| 171 | + }, |
| 172 | + { |
| 173 | + "cell_type": "code", |
| 174 | + "execution_count": null, |
| 175 | + "id": "25e86eba-4d4e-47cc-a6a7-9f0be244b009", |
| 176 | + "metadata": {}, |
| 177 | + "outputs": [], |
| 178 | + "source": [ |
| 179 | + "%%time\n", |
| 180 | + "\n", |
| 181 | + "# Train the model for 5 epochs\n", |
| 182 | + "epochs = 5\n", |
| 183 | + "\n", |
| 184 | + "model.fit(\n", |
| 185 | + " train_dataloader, # Pass the DataLoader directly\n", |
| 186 | + " epochs=epochs,\n", |
| 187 | + " verbose=1, # Print progress during training\n", |
| 188 | + ")" |
| 189 | + ] |
| 190 | + }, |
| 191 | + { |
| 192 | + "cell_type": "markdown", |
| 193 | + "id": "a0f4246c-6461-4e2a-a49d-df6c1ce770fc", |
| 194 | + "metadata": {}, |
| 195 | + "source": [ |
| 196 | + "## Visualize a Sample Prediction" |
| 197 | + ] |
| 198 | + }, |
| 199 | + { |
| 200 | + "cell_type": "code", |
| 201 | + "execution_count": null, |
| 202 | + "id": "9361cb65-3c0d-40d6-be5c-18b309626817", |
| 203 | + "metadata": {}, |
| 204 | + "outputs": [], |
| 205 | + "source": [ |
| 206 | + "# Visualize a prediction on a sample image\n", |
| 207 | + "for train_features, train_labels in train_dataloader.take(1):\n", |
| 208 | + " img = train_features[0].numpy().squeeze()\n", |
| 209 | + " label = train_labels[0].numpy()\n", |
| 210 | + " predicted_label = tf.argmax(model.predict(train_features[:1]), axis=1).numpy()[0]\n", |
| 211 | + "\n", |
| 212 | + " plt.imshow(img, cmap='gray')\n", |
| 213 | + " plt.title(f'True Label: {label}, Predicted: {predicted_label}')\n", |
| 214 | + " plt.show()\n", |
| 215 | + " break" |
| 216 | + ] |
| 217 | + }, |
| 218 | + { |
| 219 | + "cell_type": "markdown", |
| 220 | + "id": "372d0e0a-1542-4aa0-b3b9-9fd4337459ba", |
| 221 | + "metadata": {}, |
| 222 | + "source": [ |
| 223 | + "## Key Highlights \n", |
| 224 | + "\n", |
| 225 | + "- **Dynamic Batching**: Xbatcher and the MapDataset class allow for dynamic loading of batches, which reduces memory usage and speeds up data processing.\n", |
| 226 | + "- **Prefetching**: The prefetch feature in `tf.data.Dataset` overlaps data loading with model training to minimize idle time.\n", |
| 227 | + "- **Compatibility**: The pipeline works seamlessly with `keras.Model.fit`, simplifying training workflows." |
| 228 | + ] |
| 229 | + } |
| 230 | + ], |
| 231 | + "metadata": { |
| 232 | + "kernelspec": { |
| 233 | + "display_name": "Python 3 (ipykernel)", |
| 234 | + "language": "python", |
| 235 | + "name": "python3" |
| 236 | + }, |
| 237 | + "language_info": { |
| 238 | + "codemirror_mode": { |
| 239 | + "name": "ipython", |
| 240 | + "version": 3 |
| 241 | + }, |
| 242 | + "file_extension": ".py", |
| 243 | + "mimetype": "text/x-python", |
| 244 | + "name": "python", |
| 245 | + "nbconvert_exporter": "python", |
| 246 | + "pygments_lexer": "ipython3", |
| 247 | + "version": "3.11.9" |
| 248 | + } |
| 249 | + }, |
| 250 | + "nbformat": 4, |
| 251 | + "nbformat_minor": 5 |
| 252 | +} |
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