顺序消元与列主元消元C++.doc

1 实验题目用下列方法解线性方程组并比较计算结果精度（1） 顺序消元法；（2） 列主元消元法2 实验代码1. 顺序消元法#includeusing namespace std;#define N 4/方程阶数void main()double aNN=1.1348,3.8326,1.1651,3.4017,0.5301,1.7875,2.5330,1.5435,3.4129,4.9317,8.7643,1.3142,1.2371,4.9998,10.6721,0.0147;double bN=9.5342,6.3941,18.4231,16.9237;double mNN;double xN; int k,i,j; /消元计算，将方程组约化为三角形方程组for(k=0;k=N;k+)for(i=k+1;iN;i+)mik=aik/akk;for(j=k+1;jN;j+)aij-=mik*akj;bi-=mik*bk;for(i=0;iN;i+) for(j=0;jN;j+)coutaij ;coutendl; for(i=0;iN;i+) coutbi=0;i-) xi=bi;for(j=i+1;jN;j+)xi-=aij*xj;xi/=aii;/输出方程组的解 cout方程的解依次为endl;for(i=0;iN;i+)coutxi+1=xiendl;2. 列主元消元法#include#includeusing namespace std;#define N 4/方程阶数void display(double (*a)N,double *b) for(int i=0;iN;i+) for(int j=0;jN;j+)coutaij ;coutbiendl;void main()double aNN=1.1348,3.8326,1.1651,3.4017,0.5301,1.7875,2.5330,1.5435,3.4129,4.9317,8.7643,1.3142,1.2371,4.9998,10.6721,0.0147;double bN=9.5342,6.3941,18.4231,16.9237;double mNN;double xN; int k,i,j,l;double max;double p;for(k=0;kN-1;k+)max=akk;l=k; for(i=k+1;ifabs(max)max=aik; l=i;if(fabs(max)*1000001)coutdet A=0endl; elseif(l!=k)/交换行p=bl;bl=bk;bk=p;for(j=0;jN;j+)p=alj;alj=akj;akj=p;display(a,b);coutendl;for(i=k+1;iN;i+)/消元计算，将方程组约化为三角形方程组mik=aik/akk;for(j=k+1;jN;j+)aij-=mik*akj;bi-=mik*bk;display(a,b);coutendl; if(fabs(aN-1N-1)*1000001)coutdet A=0=0;i-)xi=bi;for(j=i+1;jN;j+)xi-=aij*xj;xi/=aii;/输出方程组的解