说明：  BP学习算法应用——函数表达 源代码实现了BPN的设计，使得通过训练后的BPN实现了函数表达，即BPN的输出与输入反映了特定的函数映射关系。代码中的具体应用实例为傅立叶核函数，应用BP学习算法拟合出傅立叶核函数，速度快，精度高。 将源文件F_core_discription.m文件放入matlab的work文件夹中直接运行即可。
(BP learning algorithm application- expression of the source code function BPN realize a design, through the training of BPN realize the function of expression, that is, the output and input BPN reflect a specific function mapping relations. Specific application code examples for Fourier kernel function, the application of BP learning algorithm for fitting a Fourier kernel function, high speed and accuracy. The source document file F_core_discription.m Add matlab folder of work can be directly run.)