说明：  高斯-拉盖尔积分（Gauss-laguerre积分）matlab程序，可直接在函数名前设置输出为 [x,w]= 其中x为积分点，w为权重。
(The matlab program of Gauss Laguerre integration can directly set the output to [x, w] = where x is the integration point and W is the weight in front of the function name.)