1. 最小二乘法拟合数据成直线。 2. 三次样条插值。 3. 两个3D演示程序（用程序直接在平面上画的三维图像）。-自动翻译的：1 a linear least-squares fitting the data. 2 cubic spline interpolation. 3 two 3D demo program (application directly on the painting in three-dimensional image plane).