def main():
(x_train, t_train), (x_test, t_test) = load_mnist(normalize=True,
one_hot_label=True)
x_train = x_train[:300]
t_train = t_train[:300]
max_epochs = 201
train_size = x_train.shape[0]
batch_size = 100
learning_rate = 0.01
# weight_decay_lambda = 0
weight_decay_lambda = 0.1
train_acc_list = []
test_acc_list = []
network = MultiLayerNet(input_size=784,
hidden_size_list=[100, 100, 100, 100, 100, 100],
output_size=10,
weight_decay_lambda=weight_decay_lambda)
optimizer = SGD(lr=learning_rate)
iter_per_epoch = max(train_size / batch_size, 1)
epoch_cnt = 0
for i in range(1000000000):
batch_mask = np.random.choice(train_size, batch_size)
x_batch = x_train[batch_mask]
t_batch = t_train[batch_mask]
grads = network.gradient(x_batch, t_batch)
optimizer.update(network.params, grads)
if i % iter_per_epoch == 0:
train_acc = network.accuracy(x_train, t_train)
test_acc = network.accuracy(x_test, t_test)
train_acc_list.append(train_acc)
test_acc_list.append(test_acc)
print("epoch:" + str(epoch_cnt) + ", train acc:" + str(train_acc) + \
", test acc:" + str(test_acc))
epoch_cnt += 1
if epoch_cnt >= max_epochs:
break
markers = {'train': 'o', 'test': 's'}
x = np.arange(max_epochs)
plt.plot(x, train_acc_list, marker='o', label='train', markevery=10)
plt.plot(x, test_acc_list, marker='s', label='test', markevery=10)
plt.xlabel("epochs")
plt.ylabel("accuracy")
plt.ylim(0, 1.0)
plt.legend(loc='lower right')
plt.show()
def train(train_x, train_label, test_x, test_label, learning_rate, max_epoch,
batch_size):
# weight decay（权值衰减——L2正则项强度）的设定 =======================
weight_decay_lambda = 0 # 不使用权值衰减的情况
# weight_decay_lambda = 0.1
# 构造神经网络
network = MultiLayerNet(input_size=784,
hidden_size_list=[100, 100, 100, 100, 100, 100],
output_size=10,
weight_decay_lambda=weight_decay_lambda)
optimizer = SGD(learning_rate)
train_acc_list = []
test_acc_list = []
train_size = train_x.shape[0]
iter_per_epoch = max(train_size / batch_size, 1)
batch_mask = np.arange(train_size)
np.random.shuffle(batch_mask)
epoch_cnt = 0
left = 0
iteration = int(iter_per_epoch * max_epoch)
for i in range(iteration):
# 获取一个batch的数据，更新left值
batch_x, batch_label, left = get_batch(train_x, train_label,
batch_mask, batch_size, left)
grads = network.gradient(batch_x, batch_label)
optimizer.update(network.params, grads)
# 每一个epoch记录一个在测试集上的准确率
if i % iter_per_epoch == 0:
train_acc = network.accuracy(train_x, train_label)
test_acc = network.accuracy(test_x, test_label)
train_acc_list.append(train_acc)
test_acc_list.append(test_acc)
print("epoch:" + str(epoch_cnt) + ", train acc:" + str(train_acc) +
", test acc:" + str(test_acc))
epoch_cnt += 1
return train_acc_list, test_acc_list
def __train(weight_init_std):
bn_network = MultiLayerNet(input_size=784,
hidden_size_list=[100, 100, 100, 100, 100],
output_size=10,
weight_init_std=weight_init_std,
use_batchnorm=True)
network = MultiLayerNet(input_size=784,
hidden_size_list=[100, 100, 100, 100, 100],
output_size=10,
weight_init_std=weight_init_std)
optimizer = SGD(lr=learning_rate)
train_acc_list = []
bn_train_acc_list = []
iter_per_epoch = max(train_size / batch_size, 1)
epoch_cnt = 0
for i in range(1000000000):
batch_mask = np.random.choice(train_size, batch_size)
x_batch = x_train[batch_mask]
t_batch = t_train[batch_mask]
for _network in (bn_network, network):
grads = _network.gradient(x_batch, t_batch)
optimizer.update(_network.params, grads)
if i % iter_per_epoch == 0:
train_acc = network.accuracy(x_train, t_train)
bn_train_acc = bn_network.accuracy(x_train, t_train)
train_acc_list.append(train_acc)
bn_train_acc_list.append(bn_train_acc)
print("epoch:" + str(epoch_cnt) + " | " + str(train_acc) + " - " +
str(bn_train_acc))
epoch_cnt += 1
if epoch_cnt >= max_epochs:
break
return train_acc_list, bn_train_acc_list
train_acc_list = []
test_acc_list = []
iter_per_epoch = max(train_size / batch_size, 1)
epoch_cnt = 0
for i in range(1000000000):
batch_mask = np.random.choice(train_size, batch_size)
x_batch = x_train[batch_mask]
t_batch = t_train[batch_mask]
grads = network.gradient(x_batch, t_batch)
optimizer.update(network.params, grads)
if i % iter_per_epoch == 0:
train_acc = network.accuracy(x_train, t_train)
test_acc = network.accuracy(x_test, t_test)
train_acc_list.append(train_acc)
test_acc_list.append(test_acc)
print("epoch:" + str(epoch_cnt) + ", train acc:" + str(train_acc) +
", test acc:" + str(test_acc))
epoch_cnt += 1
if epoch_cnt >= max_epochs:
break
# 绘制图形
markers = {'train': '0', 'test': 's'}
x = np.arange(max_epochs)
plt.plot(x, train_acc_list, marker='o', label='train', markevery=10)
train_acc_list = []
test_acc_list = []
iter_per_epoch = max(train_size / batch_size, 1)
epoch_cnt = 0
for i in range(1000000000):
batch_mask = np.random.choice(train_size, batch_size)
x_batch = x_train[batch_mask]
t_batch = t_train[batch_mask]
grads = network.gradient(x_batch, t_batch)
optimizer.update(network.params, grads)
if i % iter_per_epoch == 0:
train_acc = network.accuracy(x_train, t_train)
test_acc = network.accuracy(x_test, t_test)
train_acc_list.append(train_acc)
test_acc_list.append(test_acc)
print("epoch:" + str(epoch_cnt) + ", train acc:" + str(train_acc) + ", test acc:" + str(test_acc))
epoch_cnt += 1
if epoch_cnt >= max_epochs:
break
# 3.グラフの描画==========
markers = {'train': 'o', 'test': 's'}
x = np.arange(max_epochs)
plt.plot(x, train_acc_list, marker='o', label='train', markevery=10)
# 학습하면서 테스트 데이터의 정확도를 각 에포크마다 기록
train_accuracies = []
test_accuracies = []
optimizer = Sgd(learning_rate=0.01) # optimizer
for epoch in range(epochs):
# indices = np.arange(train_size)
# np.random.shuffle(indices)
for i in range(iter_per_epoch):
x_batch = X_train[(i * mini_batch_size):((i + 1) * mini_batch_size)]
y_batch = Y_train[(i * mini_batch_size):((i + 1) * mini_batch_size)]
gradients = neural_net.gradient(x_batch, y_batch)
optimizer.update(neural_net.params, gradients)
train_acc = neural_net.accuracy(X_train, Y_train)
train_accuracies.append(train_acc)
test_acc = neural_net.accuracy(X_test, Y_test)
test_accuracies.append(test_acc)
print(f'epoch #{epoch}: train={train_acc}, test={test_acc}')
x = np.arange(epochs)
plt.plot(x, train_accuracies, label='Train')
plt.plot(x, test_accuracies, label='Test')
plt.legend()
plt.title(f'Weight Decay (lambda={wd_rate})')
plt.xlabel('epoch')
plt.ylabel('accuracy')
plt.show()