程序1主要是实现正弦函数和余弦函数的线性组合，绘出两者相加后的图像。程序2、3、4中还包括罗盘图、轮廓图和填充图，从而实现这几种绘图功能。-Program is mainly a sine and cosine functions to achieve a linear combination of the two add up to draw the image. 2,3,4 program also includes compass map, contour map and fill map, in order to achieve these types of graphics.