import tensorflow as tf
import numpy as np
def add_layer(inputs,in_size,out_size,n_layer,activation_function=None): #activation_function=None线性函数
layer_name="layer%s" % n_layer
with tf.name_scope(layer_name):
with tf.name_scope('weights'):
Weights = tf.Variable(tf.random_normal([in_size,out_size])) #Weight中都是随机变量
tf.histogram_summary(layer_name+"/weights",Weights) #可视化观看变量
with tf.name_scope('biases'):
biases = tf.Variable(tf.zeros([1,out_size])+0.1) #biases推荐初始值不为0
tf.histogram_summary(layer_name+"/biases",biases) #可视化观看变量
with tf.name_scope('Wx_plus_b'):
Wx_plus_b = tf.matmul(inputs,Weights)+biases #inputs*Weight+biases
tf.histogram_summary(layer_name+"/Wx_plus_b",Wx_plus_b) #可视化观看变量
if activation_function is None:
outputs = Wx_plus_b
else:
outputs = activation_function(Wx_plus_b)
tf.histogram_summary(layer_name+"/outputs",outputs) #可视化观看变量
return outputs
#创建数据x_data,y_data
x_data = np.linspace(-1,1,300)[:,np.newaxis] #[-1,1]区间,300个单位,np.newaxis增加维度
noise = np.random.normal(0,0.05,x_data.shape) #噪点
y_data = np.square(x_data)-0.5+noise
with tf.name_scope('inputs'): #结构化
xs = tf.placeholder(tf.float32,[None,1],name='x_input')
ys = tf.placeholder(tf.float32,[None,1],name='y_input')
#三层神经,输入层(1个神经元),隐藏层(10神经元),输出层(1个神经元)
l1 = add_layer(xs,1,10,n_layer=1,activation_function=tf.nn.relu) #隐藏层
prediction = add_layer(l1,10,1,n_layer=2,activation_function=None) #输出层
#predition值与y_data差别
with tf.name_scope('loss'):
loss = tf.reduce_mean(tf.reduce_sum(tf.square(ys-prediction),reduction_indices=[1])) #square()平方,sum()求和,mean()平均值
tf.scalar_summary('loss',loss) #可视化观看常量
with tf.name_scope('train'):
train_step = tf.train.GradientDescentOptimizer(0.1).minimize(loss) #0.1学习效率,minimize(loss)减小loss误差
init = tf.initialize_all_variables()
sess = tf.Session()
#合并到Summary中
merged = tf.merge_all_summaries()
#选定可视化存储目录
writer = tf.train.SummaryWriter("Desktop/",sess.graph)
sess.run(init) #先执行init
#训练1k次
for i in range(1000):
sess.run(train_step,feed_dict={xs:x_data,ys:y_data})
if i%50==0:
result = sess.run(merged,feed_dict={xs:x_data,ys:y_data}) #merged也是需要run的
writer.add_summary(result,i) #result是summary类型的,需要放入writer中,i步数(x轴)
声明:本网转发此文章,旨在为读者提供更多信息资讯,所涉内容不构成投资、消费建议。文章事实如有疑问,请与有关方核实,文章观点非本网观点,仅供读者参考。