|
| 1 | +using Makina.Layers; |
| 2 | +using NumSharp; |
| 3 | +using System; |
| 4 | +using System.Collections.Generic; |
| 5 | +using System.Text; |
| 6 | +using Tensorflow; |
| 7 | +using static Makina.Makina; |
| 8 | +using static Tensorflow.Python; |
| 9 | + |
| 10 | +namespace Makina |
| 11 | +{ |
| 12 | + public class Model |
| 13 | + { |
| 14 | + public Tensor Flow; |
| 15 | + List<ILayer> layer_stack; |
| 16 | + |
| 17 | + public TensorShape InputShape; |
| 18 | + |
| 19 | + public Model() |
| 20 | + { |
| 21 | + layer_stack = new List<ILayer>(); |
| 22 | + } |
| 23 | + public Model Add(ILayer layer) |
| 24 | + { |
| 25 | + layer_stack.Add(layer); |
| 26 | + return this; |
| 27 | + } |
| 28 | + public Model Add(IEnumerable<ILayer> layers) |
| 29 | + { |
| 30 | + layer_stack.AddRange(layers); |
| 31 | + return this; |
| 32 | + } |
| 33 | + public Tensor getFlow() |
| 34 | + { |
| 35 | + try |
| 36 | + { |
| 37 | + return Flow; |
| 38 | + } |
| 39 | + catch (Exception ex) |
| 40 | + { |
| 41 | + return null; |
| 42 | + } |
| 43 | + } |
| 44 | + public (Operation, Tensor, Tensor) make_graph(Tensor features, Tensor labels) |
| 45 | + { |
| 46 | + |
| 47 | + // TODO : Creating Loss Functions And Optimizers..... |
| 48 | + |
| 49 | + #region Model Layers Graph |
| 50 | + /* |
| 51 | + var stddev = 1 / Math.Sqrt(2); |
| 52 | +
|
| 53 | + var d1 = new Dense(num_hidden); |
| 54 | + d1.__build__(features.getShape()); |
| 55 | + var hidden_activations = tf.nn.relu(d1.__call__(features)); |
| 56 | +
|
| 57 | + var d1_output = d1.output_shape(features.getShape()); |
| 58 | + |
| 59 | +
|
| 60 | + var d2 = new Dense(1); |
| 61 | + d2.__build__(d1.output_shape(features.getShape()), seed: 17, stddev: (float)(1/ Math.Sqrt(num_hidden))); |
| 62 | + var logits = d2.__call__(hidden_activations); |
| 63 | + var predictions = tf.sigmoid(tf.squeeze(logits)); |
| 64 | + */ |
| 65 | + #endregion |
| 66 | + |
| 67 | + #region Model Graph Form Layer Stack |
| 68 | + var flow_shape = features.getShape(); |
| 69 | + Flow = features; |
| 70 | + for (int i = 0; i < layer_stack.Count; i++) |
| 71 | + { |
| 72 | + layer_stack[i].__build__(flow_shape); |
| 73 | + flow_shape = layer_stack[i].output_shape(flow_shape); |
| 74 | + Flow = layer_stack[i].__call__(Flow); |
| 75 | + } |
| 76 | + var predictions = tf.sigmoid(tf.squeeze(Flow)); |
| 77 | + |
| 78 | + #endregion |
| 79 | + |
| 80 | + #region loss and optimizer |
| 81 | + var loss = tf.reduce_mean(tf.square(predictions - tf.cast(labels, tf.float32)), name: "loss"); |
| 82 | + |
| 83 | + var gs = tf.Variable(0, trainable: false, name: "global_step"); |
| 84 | + var train_op = tf.train.GradientDescentOptimizer(0.2f).minimize(loss, global_step: gs); |
| 85 | + #endregion |
| 86 | + |
| 87 | + return (train_op, loss, gs); |
| 88 | + } |
| 89 | + public float train(int num_steps, (NDArray, NDArray) training_dataset) |
| 90 | + { |
| 91 | + var (X, Y) = training_dataset; |
| 92 | + var x_shape = X.shape; |
| 93 | + var batch_size = x_shape[0]; |
| 94 | + var graph = tf.Graph().as_default(); |
| 95 | + |
| 96 | + var features = tf.placeholder(tf.float32, new TensorShape(batch_size, 2)); |
| 97 | + var labels = tf.placeholder(tf.float32, new TensorShape(batch_size)); |
| 98 | + |
| 99 | + var (train_op, loss, gs) = this.make_graph(features, labels); |
| 100 | + |
| 101 | + var init = tf.global_variables_initializer(); |
| 102 | + |
| 103 | + float loss_value = 0; |
| 104 | + with(tf.Session(graph), sess => |
| 105 | + { |
| 106 | + sess.run(init); |
| 107 | + var step = 0; |
| 108 | + |
| 109 | + |
| 110 | + while (step < num_steps) |
| 111 | + { |
| 112 | + var result = sess.run( |
| 113 | + new ITensorOrOperation[] { train_op, gs, loss }, |
| 114 | + new FeedItem(features, X), |
| 115 | + new FeedItem(labels, Y)); |
| 116 | + loss_value = result[2]; |
| 117 | + step = result[1]; |
| 118 | + if (step % 1000 == 0) |
| 119 | + Console.WriteLine($"Step {step} loss: {loss_value}"); |
| 120 | + } |
| 121 | + Console.WriteLine($"Final loss: {loss_value}"); |
| 122 | + }); |
| 123 | + |
| 124 | + return loss_value; |
| 125 | + } |
| 126 | + } |
| 127 | +} |
0 commit comments