Week4:Neural Networks难点记录

为什么θ的维度是S_j+1*(S_j+1)?

课堂PPT没有两层单元个数不同的状态，故举一个例子就知道了

Example: If layer 1 has 2 input nodes and layer 2 has 4 activation nodes. Dimension of Θ(1) is going to be 4×3 where s_j=2 and s_j+1=4, so s_j+1×(s_j+1)=4×3.

 

编程作业: Multi-class Classification and Neural Networks难点记录

1.displayData函数工作原理

 2.fmincg的工作原理