def test_argmax(): x = tf.placeholder(tf.float32) y = tf.argmax(x, 1) ax = np.random.uniform(size=(700, 10)) sess = tf.Session() ay = sess.run(y, feed_dict={x:ax}) npy = np.argmax(ax, 1) assert(np.mean(np.abs(ay - npy))) < 1e-6
from tinyflow.datasets import get_mnist # Create the model x = tf.placeholder(tf.float32, [None, 784]) W = tf.Variable(tf.zeros([784, 10])) y = tf.nn.softmax(tf.matmul(x, W)) # Define loss and optimizer y_ = tf.placeholder(tf.float32, [None, 10]) cross_entropy = tf.reduce_mean(-tf.reduce_sum(y_ * tf.log(y), reduction_indices=[1])) learning_rate = 0.5 W_grad = tf.gradients(cross_entropy, [W])[0] train_step = tf.assign(W, W - learning_rate * W_grad) sess = tf.Session() sess.run(tf.initialize_all_variables()) # get the mnist dataset mnist = get_mnist(flatten=True, onehot=True) for i in range(1000): batch_xs, batch_ys = mnist.train.next_batch(100) sess.run(train_step, feed_dict={x: batch_xs, y_:batch_ys}) correct_prediction = tf.equal(tf.argmax(y,1), tf.argmax(y_,1)) accuracy = tf.reduce_mean(correct_prediction) print(sess.run(accuracy, feed_dict={x: mnist.test.images, y_: mnist.test.labels}))
feed_dict=known_shape): init_step.append(tf.assign(v, tf.normal(shape, stdev))) print("shape[%s]=%s" % (name, str(shape))) sess.run(init_step) # get the mnist dataset mnist = get_mnist(flatten=False, onehot=False) print_period = 1000 for epoch in range(10): sum_loss = 0.0 num_batch = 600 for i in range(num_batch): batch_xs, batch_ys = mnist.train.next_batch(100) loss, _ = sess.run([cross_entropy, train_step], feed_dict={ x: batch_xs, label: batch_ys }) sum_loss += loss print("epoch[%d] cross_entropy=%g" % (epoch, sum_loss / num_batch)) correct_prediction = tf.equal(tf.argmax(fc2, 1), label) accuracy = tf.reduce_mean(correct_prediction) print( sess.run(accuracy, feed_dict={ x: mnist.test.images, label: mnist.test.labels }))
cross_entropy = tf.nn.mean_sparse_softmax_cross_entropy_with_logits(fc2, label) train_step = tf.train.GradientDescentOptimizer(0.5).minimize(cross_entropy) sess = tf.Session(device='gpu') # Automatic variable shape inference API, infers the shape and initialize the weights. known_shape = {x: [100, 28 * 28], label: [100]} init_step = [] for v, name, shape in tf.infer_variable_shapes( cross_entropy, feed_dict=known_shape): init_step.append(tf.assign(v, tf.normal(shape))) print("shape[%s]=%s" % (name, str(shape))) sess.run(init_step) # get the mnist dataset mnist = get_mnist(flatten=True, onehot=False) print_period = 1000 for epoch in range(10): sum_loss = 0.0 num_batch = 600 for i in range(num_batch): batch_xs, batch_ys = mnist.train.next_batch(100) loss, _ = sess.run([cross_entropy, train_step], feed_dict={x: batch_xs, label:batch_ys}) sum_loss += loss print("epoch[%d] cross_entropy=%g" % (epoch, sum_loss /num_batch)) correct_prediction = tf.equal(tf.argmax(fc2, 1), label) accuracy = tf.reduce_mean(correct_prediction) print(sess.run(accuracy, feed_dict={x: mnist.test.images, label: mnist.test.labels}))
W = tf.Variable(tf.zeros([784, 10])) y = tf.nn.softmax(tf.matmul(x, W)) # Define loss and optimizer y_ = tf.placeholder(tf.float32, [None, 10]) cross_entropy = tf.reduce_mean( -tf.reduce_sum(y_ * tf.log(y), reduction_indices=[1])) train_step = tf.train.GradientDescentOptimizer(0.5).minimize(cross_entropy) sess = tf.Session() sess.run(tf.initialize_all_variables()) # get the mnist dataset mnist = get_mnist(flatten=True, onehot=True) print("minist download is completed!") for i in range(1000): batch_xs, batch_ys = mnist.train.next_batch(100) sess.run(train_step, feed_dict={x: batch_xs, y_: batch_ys}) correct_prediction = tf.equal(tf.argmax(y, 1), tf.argmax(y_, 1)) accuracy = tf.reduce_mean(correct_prediction) print( sess.run(accuracy, feed_dict={ x: mnist.test.images, y_: mnist.test.labels }))