Tensorflow——MNIST手書きデジタルデータセット識別分類、精度98%以上の方法実験
6378 ワード
1、ネットワーク設計まず,MNISTデータセットを訓練するネットワークとして,2層の隠蔽層を有するニューラルネットワークを設計した. 学習率を変数に設定する(反復ごとに、収束速度をより速くするために式によって小学校の学習率を減らす). はDropoutアルゴリズムを導入するが、それを使用しない(keep_probは1.0に設定されている)ため、この項目も変更可能であり、精度に一定の影響を及ぼすことを説明するためだけである. クロスエントロピー代価関数を用いてloss を計算する Adamオプティマイザを使用してlossを動作させ、lossが最小 になるようにする.
2、ネットワークの実現
ネットワークは次のとおりです.
3、テスト結果
出力結果:
2、ネットワークの実現
ネットワークは次のとおりです.
import tensorflow as tf
from tensorflow.examples.tutorials.mnist import input_data
#
mnist = input_data.read_data_sets("MNIST_data",one_hot=True)
#
batch_size = 100
#
n_batch = mnist.train.num_examples // batch_size
# (placeholder)
x = tf.placeholder(tf.float32,[None,784])
y = tf.placeholder(tf.float32,[None,10])
# placeholder, Dropout
keep_prob = tf.placeholder(tf.float32)
#
lr = tf.Variable(0.001,dtype= tf.float32)
#
#
#
W1 = tf.Variable(tf.truncated_normal([784,500],stddev = 0.1)) # , :stddev
#
b1 = tf.Variable(tf.zeros([500]) + 0.1)
# , ,
L1 = tf.nn.tanh(tf.matmul(x, W1) + b1)
# tensorflow dropout ,keep_prob , , feed
L1_drop = tf.nn.dropout(L1, keep_prob)
# :2000
W2 = tf.Variable(tf.truncated_normal([500,300],stddev = 0.1))
b2 = tf.Variable(tf.zeros([300]) + 0.1)
L2 = tf.nn.tanh(tf.matmul(L1_drop, W2) + b2)
L2_drop = tf.nn.dropout(L2, keep_prob)
# :10
W3 = tf.Variable(tf.truncated_normal([300,10],stddev = 0.1))
b3 = tf.Variable(tf.zeros([10]) + 0.1)
prediction = tf.nn.softmax(tf.matmul(L2_drop,W3) + b3)
# (cross-entropy)
loss = tf.reduce_mean(tf.nn.softmax_cross_entropy_with_logits(labels=y, logits=prediction))
# Adam
train_step = tf.train.AdamOptimizer(lr).minimize(loss)
#
init = tf.global_variables_initializer()
#
#equal , , True, False。argmax : ,
correct_prediction = tf.equal(tf.argmax(y,1),tf.argmax(prediction,1))
#
# 32 , True 1.0,False 0.0,
accuracy = tf.reduce_mean(tf.cast(correct_prediction,tf.float32))
#
with tf.Session() as sess:
#
sess.run(init)
# 21
for epoch in range(51):
# , , : , , , loss
sess.run(tf.assign(lr,0.001*(0.95**epoch)))
#n_batch:
for batch in range(n_batch):
# 100 , batch_xs , batch_ys
batch_xs,batch_ys = mnist.train.next_batch(batch_size)
# Feed , op, ,keep_prob 1.0 Dropout
sess.run(train_step,feed_dict = {x:batch_xs,y:batch_ys,keep_prob:1.0})
learning_rate = sess.run(lr)
# , Feed , op ,
test_acc = sess.run(accuracy,feed_dict = {x:mnist.test.images,y:mnist.test.labels,keep_prob:1.0})
print("Iter " + str(epoch) + ",Testing Accuracy " + str(test_acc) + ", Learning Rate= " + str(learning_rate))
3、テスト結果
出力結果:
Extracting MNIST_data/train-images-idx3-ubyte.gz
Extracting MNIST_data/train-labels-idx1-ubyte.gz
Extracting MNIST_data/t10k-images-idx3-ubyte.gz
Extracting MNIST_data/t10k-labels-idx1-ubyte.gz
Iter 0,Testing Accuracy 0.9499, Learning Rate= 0.001
Iter 1,Testing Accuracy 0.9645, Learning Rate= 0.00095
Iter 2,Testing Accuracy 0.968, Learning Rate= 0.0009025
Iter 3,Testing Accuracy 0.9708, Learning Rate= 0.000857375
Iter 4,Testing Accuracy 0.9747, Learning Rate= 0.00081450626
Iter 5,Testing Accuracy 0.9761, Learning Rate= 0.0007737809
Iter 6,Testing Accuracy 0.9746, Learning Rate= 0.0007350919
Iter 7,Testing Accuracy 0.9791, Learning Rate= 0.0006983373
Iter 8,Testing Accuracy 0.9757, Learning Rate= 0.0006634204
Iter 9,Testing Accuracy 0.9797, Learning Rate= 0.0006302494
Iter 10,Testing Accuracy 0.9773, Learning Rate= 0.0005987369
Iter 11,Testing Accuracy 0.9795, Learning Rate= 0.0005688001
Iter 12,Testing Accuracy 0.9786, Learning Rate= 0.0005403601
Iter 13,Testing Accuracy 0.9801, Learning Rate= 0.0005133421
Iter 14,Testing Accuracy 0.9807, Learning Rate= 0.000487675
Iter 15,Testing Accuracy 0.9806, Learning Rate= 0.00046329122
Iter 16,Testing Accuracy 0.9814, Learning Rate= 0.00044012666
Iter 17,Testing Accuracy 0.9807, Learning Rate= 0.00041812033
Iter 18,Testing Accuracy 0.9802, Learning Rate= 0.00039721432
Iter 19,Testing Accuracy 0.9817, Learning Rate= 0.0003773536
Iter 20,Testing Accuracy 0.9807, Learning Rate= 0.00035848594
Iter 21,Testing Accuracy 0.9804, Learning Rate= 0.00034056162
Iter 22,Testing Accuracy 0.9801, Learning Rate= 0.00032353355
Iter 23,Testing Accuracy 0.9814, Learning Rate= 0.00030735688
Iter 24,Testing Accuracy 0.9818, Learning Rate= 0.000291989
Iter 25,Testing Accuracy 0.9821, Learning Rate= 0.00027738957
Iter 26,Testing Accuracy 0.981, Learning Rate= 0.0002635201
Iter 27,Testing Accuracy 0.9818, Learning Rate= 0.00025034408
Iter 28,Testing Accuracy 0.9826, Learning Rate= 0.00023782688
Iter 29,Testing Accuracy 0.9822, Learning Rate= 0.00022593554
Iter 30,Testing Accuracy 0.9824, Learning Rate= 0.00021463877
Iter 31,Testing Accuracy 0.9811, Learning Rate= 0.00020390682
Iter 32,Testing Accuracy 0.9818, Learning Rate= 0.00019371149
Iter 33,Testing Accuracy 0.9815, Learning Rate= 0.0001840259
Iter 34,Testing Accuracy 0.9814, Learning Rate= 0.00017482461
Iter 35,Testing Accuracy 0.9818, Learning Rate= 0.00016608338
Iter 36,Testing Accuracy 0.9823, Learning Rate= 0.00015777921
Iter 37,Testing Accuracy 0.9828, Learning Rate= 0.00014989026
Iter 38,Testing Accuracy 0.9818, Learning Rate= 0.00014239574
Iter 39,Testing Accuracy 0.9813, Learning Rate= 0.00013527596
Iter 40,Testing Accuracy 0.9815, Learning Rate= 0.00012851215
Iter 41,Testing Accuracy 0.9815, Learning Rate= 0.00012208655
Iter 42,Testing Accuracy 0.9813, Learning Rate= 0.00011598222
Iter 43,Testing Accuracy 0.9811, Learning Rate= 0.00011018311
Iter 44,Testing Accuracy 0.9815, Learning Rate= 0.000104673956
Iter 45,Testing Accuracy 0.9813, Learning Rate= 9.944026e-05
Iter 46,Testing Accuracy 0.9822, Learning Rate= 9.446825e-05
Iter 47,Testing Accuracy 0.9813, Learning Rate= 8.974483e-05
Iter 48,Testing Accuracy 0.9817, Learning Rate= 8.525759e-05
Iter 49,Testing Accuracy 0.9823, Learning Rate= 8.099471e-05
Iter 50,Testing Accuracy 0.9816, Learning Rate= 7.6944976e-05