GM_1_1

代码说明：

  灰色gm(1,1)模型，当做函数可以调用，中间注释写得很详细，稍加修改即可成为灰色系统中别的算法。(Gray gm (1,1) model, as a function can call the Notes between very detailed, a little modification to the system as a gray-level algorithm.)