C 代码 计算并写出 用于近似积分的高斯-拉盖尔正交规则 密度 exp（-x） 在区间 [0，+oo） 上的函数.rar

20 January 2020 01:01:47 PM LAGUERRE_RULE C version Compute a Gauss-Laguerre quadrature rule for Integral ( A <= x < +oo ) exp(-b*(x-a)) f(x) dx of order N. The user specifies N, A, B, and FILENAME. N is the number of points; A is the left endpoint, usually 0.0: B is a scale factor, usually 1.0; FILENAME is used to generate 3 files: * filename_w.txt - the weight file * filename_x.txt - the abscissa file. * filename_r.txt - the region file. N = 4 A = 0 B = 1 FILENAME = "lag_o4" Creating quadrature files. Root file name is "lag_o4" Weight file will be "lag_o4_w.txt" Abscissa file will be "lag_o4_x.txt" Region file will be "lag_o4_r.txt" LAGUERRE_RULE: Normal end of execution. 20 January 2020 01:01:47 PM