最小二乘法2次曲线拟合应用已有的采样时间点，再现这些点所描述的2次曲线的变化，即求出一个二次曲线方程y=ax2+bx+c这个算法的主要问题也就是如何用给定的数据求方程系数abc-Least squares curve fitting application 2 has a sampling time points, reproduce these points 2 are described the change curve, which obtained a quadratic equatio