% Gauss-Laguerre integration
ex =input(' number of nodes, 2, 4 or 8 ? ')
 if ex==2
W=[.853553390593274 .146446609406726];
X=[.585786437626905  3.41421356237310];
elseif ex==4
W=[.603154104341634 .3574186924378 .0388879085150054 ...
.539294705561327e-3];
X=[.322547689619392 1.74576110115835 4.53662029692113 ...
9.39507091230113];
elseif ex==8
W=[.369188589341638 .418786780814343 .175794986637172 ...
.0333434922612157 .279453623522567e-2 .907650877335821e-4 ...
.848574671627253e-6 .104800117487151e-8];
X=[.170279632305101 0.90370177679938 2.25108662986613 ...
4.26670017028766 7.04590540239347 10.758516010181 ...
15.740678641278 22.8631317368893];
else
  disp ('no data for this n')
end