import tensorflow as tf
import numpy as np
def add_layer(inputs, in_size, out_size, activation_function=):
Weights = tf.Variable(tf.random_normal([in_size, out_size]))
biases = tf.Variable(tf.zeros([1, out_size]) + 0.1)
Wx_plus_b = tf.matmul(inputs, Weights) + biases
if activation_function is None:
outputs = Wx_plus_b
else:
outputs = activation_function(Wx_plus_b)
return outputs
x_data = np.linspace(-1,1,10, dtype=np.float32)[:, np.newaxis]
#noise = np.random.normal(0, 0.05, x_data.shape).astype(np.float32)
y_data = x_data #- 0.5 #+ noise
# print(type(x_data))
# print(y_data)
xs = tf.placeholder(tf.float32, [None, 1])
ys = tf.placeholder(tf.float32, [None, 1])
l1 = add_layer(xs, 1, 10, activation_function=tf.nn.relu)
prediction = add_layer(l1, 10, 1, activation_function=None)
loss = tf.reduce_mean(tf.reduce_sum(tf.square(ys - prediction),
reduction_indices=[1]))
train_step = tf.train.GradientDescentOptimizer(0.1).minimize(loss)
# init = tf.initialize_all_variables() # tf 马上就要废弃这种写法
init = tf.global_variables_initializer() # 替换成这样就好
sess = tf.Session()
sess.run(init)
#for i in range(0):
# training
print(sess.run(loss, feed_dict={xs: x_data, ys: y_data}))
sess.run(train_step, feed_dict={xs: x_data, ys: y_data})
# to see the step improvement
print(sess.run(loss, feed_dict={xs: x_data, ys: y_data}))
sess.run(train_step, feed_dict={xs: x_data, ys: y_data})
# to see the step improvement
print(sess.run(loss, feed_dict={xs: x_data, ys: y_data}))
sess.run(train_step, feed_dict={xs: x_data, ys: y_data})
# to see the step improvement
print(sess.run(loss, feed_dict={xs: x_data, ys: y_data}))
import matplotlib.pyplot as plt
# plot the real data
fig = plt.figure()
ax = fig.add_subplot(1,1,1)
ax.scatter(x_data, y_data)
plt.ion()#本次运行请注释,全局运行不要注释
plt.show()
for i in range(1000):
# training
sess.run(train_step, feed_dict={xs: x_data, ys: y_data})
if i % 50 == 0:
# to visualize the result and improvement
try:
ax.lines.remove(lines[0])
except Exception:
pass
prediction_value = sess.run(prediction, feed_dict={xs: x_data})
# plot the prediction
lines = ax.plot(x_data, prediction_value, 'r-', lw=5)
plt.pause(0.1)