生成数据
import numpy as np
import tensorflow as tf
import matplotlib.pyplot as plt
num_points=1000
vectors_set=[]
for i in range(num_points):
x1 = np.random.normal(0.0,0.55)
y1 = x1*0.1+0.3+np.random.normal(0.0,0.03)
vectors_set.append([x1,y1])
x_data = [v[0] for v in vectors_set]
y_data = [v[1] for v in vectors_set]
plt.scatter(x_data,y_data,c='r')
plt.show()
拟合数据
W=tf.Variable(tf.random_uniform([1],-1.0,1.0),name='W')
b=tf.Variable(tf.zeros[1],name='b')
y=W*x_data+b
loss=tf.reduce_mean(tf.square(y-y_data),name='loss')
optimizer=tf.train.GradientDescentOptimizer(0.5) # 梯度下降算法
train=optimizer.minimize(loss,name='train')
sess=tf.Session()
init=tf.global_variables_initializer()
sess.run(init)
print("W=",sess.run(W),"b=",sess.run(b),"loss=",sess.run(loss))
for step in range(20):
sess.run(train)
print("W=",sess.run(W),"b=",sess.run(b),"loss=",sess.run(loss))
writer=tf.train.SummaryWriter("./tmp",sess.graph)
绘制模型
plt.scatter(x_data,y_data,c='r')
plt.plot(x_data,sess.run(W)*x_data+sess.run(b))
plt.show()
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