从随机的数据中找出其规律性，给出其近似表达式的问题，在生产实践和科学实验中大量存在，通常利用数据的最小二乘法求得拟合曲线。-From random data to find its regularity, give its approximate expression problems in the production practice and scientific experiments abound, often use the data obtained by least squares curve fitting.