tensorflow.placeholder

# 속성 3개
# 중간층 2개(10)
# placeholder 적용
from sklearn.datasets import load_iris
iris=load_iris()
X=tf.placeholder(tf.float32,shape=(None,3))
y=tf.placeholder(tf.float32,shape=(None,1))

w=tf.Variable(tf.random.normal([3,5]))
b=tf.Variable(tf.random.normal([5]))

u=tf.nn.relu(X@w+b)
# 150x5
ww=tf.Variable(tf.random.normal([5,5]))
bb=tf.Variable(tf.random.normal([5]))

uu=tf.nn.relu(u@ww+bb)

www=tf.Variable(tf.random.normal([5,1]))
bbb=tf.Variable(tf.random.normal([1]))

pred_y=uu@www+bbb

mse=tf.reduce_mean(tf.square(y-pred_y))

optimizer = tf.train.GradientDescentOptimizer(learning_rate=0.001)
train_op=optimizer.minimize(mse)

costs=[]

tf.global_variables_initializer().run()

for i in range(300):
    mse_val,_=sess.run([mse,train_op],feed_dict={X:iris.data[:,[0,1,2]],y:iris.data[:,[3]]})
    costs.append(mse_val)
plt.plot(costs)