1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
| import tensorflow as tf import numpy as np import matplotlib.pyplot as plt
def add_layer(inputs, in_size, out_size, activation_function = None): 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(-1,1,300)[:,np.newaxis] noise = np.random.normal(0,0.05,x_data.shape) y_data = np.square(x_data) - 0.5 + noise
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() init = tf.global_variables_initializer()
sess = tf.Session() sess.run(init)
fig = plt.figure() ax = fig.add_subplot(1,1,1) ax.scatter(x_data,y_data)
plt.ion() plt.show() # plt.close()
for i in range(1000): sess.run(train_step,feed_dict={xs:x_data,ys:y_data}) if i % 50 == 0: # print(sess.run(loss,feed_dict={xs:x_data,ys:y_data}))
try: ax.lines.remove(lines[0]) except Exception: pass
prediction_value = sess.run(prediction,feed_dict={xs:x_data}) lines = ax.plot(x_data,prediction_value,'r-',lw = 3) plt.pause(0.5)
|