改进的BP神经网络算法，基于拟牛顿算法。-Improved BP neural network algorithm, based on the quasi-Newton algorithm.

BP神经网络的C++算法实现及讨论。通过C++构造一个5层神经网络，成功实现样本函数的功能。-C++ BP neural network algorithm to achieve and discussion. By C++ construct a five-layer neural network, the successful implementation of functional sample function.