선형근사.py

import numpy as np
number_of_points=500                                               #수행횟수
x_point=[]                                                         # X랜덤변수 배열
y_point=[]
a=0.22
b=0.78
x=-1.5
x_po=[]
for i in range(number_of_points):
    x=x+0.006
    x_po.append([x])                          
    y=a*x+b+np.random.normal(0.0,0.1)
    x_point.append([x])
    y_point.append([y])
import matplotlib.pyplot as plt
plt.plot(x_point,y_point, 'o', label='Input Data')
plt.legend()
plt.show()

import tensorflow as tf
A=tf.Variable(tf.random_uniform([1],-1.0,1.0))
B=tf.Variable(tf.zeros([1]))
y=A*x_point+B
cost_function=tf.reduce_mean(tf.square(y-y_point))
optimizer=tf.train.GradientDescentOptimizer(0.5)
train=optimizer.minimize(cost_function)
model=tf.global_variables_initializer()
with tf.Session() as session:
    session.run(model)
    for step in range(0,101):
        session.run(train)
        if (step % 5) ==0:
            plt.plot(x_point,y_point,'o',label='step={}'.format(step))
            plt.plot(x_po,session.run(A)*x_po+session.run(B))
            plt.legend()
            plt.show()
            print(session.run(A),session.run(B))