非线性映射能力：BP神经网络实质上实现了一个从输入到输出的映射功能，数学理论证明三层的神经网络就能够以任意精度逼近任何非线性连续函数。这使得其特别适合于求解内部机制复杂的问题，即BP神经网络具有较强的非线性映射能力-Nonlinear mapping ability: BP neural network essentially implements a mapping from input to output function, the mathematical proof of the three neural network can approximate any nonlinear arbitrary precision continuous function. This makes it particularly suitable for solving complex problems internal mechanism that BP neural network has strong nonlinear mapping ability