import numpy as np
print("--------w---------")
w=np.array([[1,2,3],[4,5,6]])
print(w)
print(w.shape)
print("--------x---------")
x=np.array([[2,3],[4,5],[6,7]])
print(x)
print(x.shape)
print("--------y_pre---------")
y_pre=w.dot(x)
print(y_pre)
print(y_pre.shape)
x= np.array([1, 2, 3, 4, 5, 6]).reshape(2, 3)
print(x)
import numpy as np
# 使用arange创建序列，再reshape
x = np.arange(1, 7).reshape(2, 3)
print(x)
# --------w---------
# [[1 2 3]
# [4 5 6]]
# (2, 3)
# --------x---------
# [[2 3]
# [4 5]
# [6 7]]
# (3, 2)
# --------y_pre---------
# [[28 34]
# [64 79]]
# (2, 2)
N = 150
D_in = 4
H = 6
D_out =3 # 150条数据，4维度，隐层神经元6，输出2类
# Iris鸢尾花数据集 https://cuc.yingshinet.com/V7/CH10/irisKmeans.htm
x = np.random.randn(N, D_in) #均值为0，方差为1的随机数，值在[-3,3]之间
print(x[0])
print(x.shape)
w = np.random.randn(D_in,H)
print(w[0])
print(w.shape)
y_pre=x.dot(w)
print(y_pre[0])
print(y_pre.shape)
Iris数据集