工程实验数据的非线性拟合方法

Nonlinear fitting method for engineering experimental data

在EXCEL软件中,拟合非线性实验数据有4种方法。其中规划求解方法与随机抽样方法的最大优点是不要变换方程,且适合任何实验数据非线性拟合。规划求解方法最为简便,但精度相对要差,结果有时难以把握。后者加入了VBA混合编程,达到筛选与优化目的,提高了拟合精度。另2种方法为函数公式方法和回归分析方法,前者根据最小二乘法原理仅仅在电子表格中输入函数公式即可得到精度极高的拟合结果。后者利用了EXCEL自带的数学分析工具完成拟合,精度最高。但它们在应用之前,需要对实验数据进行多元多项式方程变换,对难于变换的非线性实验数据不适合。处理工程实验数据,掌握这4种非线性实验数据的拟合方法很有必要。

The Microsoft EXCEL provided four methods with nonlinear experimental data fitting. The advantages of the first importance of programming calculation ＆ random sampling method are no need to transform the equation and suitable for non-linear fitting of any data. The programming calculation method is simple and its accuraey is poor, relatively and sometimes the results are difficult to make sure of. The latter are combined with the VBA mixed programming to achieve the purpose of screening and optimization and improved the fitting precision. The next two methods are EXCEL function formula and regression analysis method. The former can get fitting result of high precision by function formula inputting based on the principle of least squares. The latter is with the highest fitting accuracy by the use of EXCEL mathematical analysis tools. Hewer, before the application of both of these methods, multivariate polynomial equation transformation of data is required .It is natural that both of these methods are not suitable for nonlinear experimental data which is difficult to transform and it is necessary to grasp these four non-lineer fitting method process experimental data of projects.