符号微分求解系统的原理与实现

On Principle and Realization of Symbol Derivatives Problem Solving System

本文分析初等函数及其导函数之间的数据结构联系,用C语言开发出实用的符号微分求解系统。本系统可以会话方式对初等函数表达式给出相应的导函数,亦可以批处理方式产生以初等函数表示的非线性问题中的梯度表达式的函数子程序源文件。函数表达式可以用C、Fortran语言描述。该系统的会话方式应用于《高等数学》课程的CAI,批处理方式应用于电力系统潮流计算中Jacobi矩阵子程序源文件的自动生成,均收到了很好的效果。

The data stracture relations between primary function and their derivatives are analyzed, and a practical system, based on C language, for symbol derivative is developed. The system can generate corresponding derivative for any primary function. It works in both dialog mode, used for Computer-Assisted Instruction (CAI), and batch mode used for producing the source code file of Jacobian matrix containing gradient information. Primary fanctions could be written in C or FORTRAN language. The performance is validated by computation practice in power system.