import numpy as np

#定義X，W1，B1
X = np.array([1.0, 0.5])
w1 = np.array([[0.1, 0.3, 0.5],[0.2, 0.4, 0.6]])
b1 = np.array([0.1, 0.2, 0.3])

#查看他們的形狀
print(X.shape)
print(w1.shape)
print(b1.shape)

#求點積
np.dot(X,w1)

def sigmod(x):
    return 1/(1 + np.exp(-x))
Z1 = sigmod(A1)
Z1

#定義w2，b2
w2 = np.array([[0.1,0.4],[0.2,0.5],[0.3,0.6]])
b2 = np.array([0.1,0.2])

#查看他們的行狀
print(w2.shape)
print(b2.shape)

A2 = np.dot(Z1,w2) + b2
A2

Z2 = sigmod(A2)
Z2

#定義恒等函數(shù)

def identity_function(x):
    return x

#定義w3,b3
w3 = np.array([[0.1,0.3],[0.2,0.4]])
b3 = np.array([0.1,0.2])

A3 = np.dot(Z2,w3) + b3
Y = identity_function(A3)
Y
    

#整理

#定義一個字典，將權重全部放入字典
def init_network():
    network = {}
    network['w1'] = np.array([[0.1,0.3,0.5],[0.2,0.4,0.6]])
    network['w2'] = np.array([[0.1,0.4],[0.2,0.5],[0.3,0.6]])
    network['w3'] = np.array([[0.1,0.3],[0.2,0.4]])
    network['b1'] = np.array([0.1, 0.2, 0.3])
    network['b2'] = np.array([0.1,0.2])
    network['b3'] = np.array([0.1,0.2])
    return network

#定義函數(shù)，導入權重與x，得到Y

def forward(network,x):
    w1,w2,w3 = network['w1'],network['w2'],network['w3']
    b1,b2,b3 = network['b1'],network['b2'],network['b3']
    
    A1 = np.dot(x,w1) + b1
    A2 = np.dot(A1,w2) + b2
    A3 = np.dot(A2,w3) + b3
    Y = identity_function(A3)
    Y

#調(diào)用函數(shù)

network = init_network()
X = np.array([1.0,0.5])
Y = forward(network,X)