tri_matrix.cpp

一维ADiFDTD算法的改进

#include<stdio.h>
#include<math.h>
#include<fstream.h>

int tri_matrix(int n, double *a, double *b, double *c, double *f);

void main()
{ int n,k;
    n=5;
	double *a=new double[6];
	double *b=new double[6];
	double *c=new double[6];
	double *f=new double[6];
	
    for(k=0;k<5;k++)	a[k]=0.0;
	for(k=0;k<5;k++)	b[k]=0.0;
	for(k=0;k<5;k++)	c[k]=0.0;
	for(k=0;k<5;k++)	f[k]=0.0;

	a[0]=1.0; a[1]=1.0; a[2]=1.0; a[3]=1.0;a[4]=1.0;a[5]=100.;
	b[0]=1.0; b[1]=2.0; b[2]=3.0; b[3]=4.0; b[4]=5.0;b[5]=100.0;
	c[0]=1.0; c[1]=1.0; c[2]=1.0; c[3]=1.0; c[4]=1.0;c[5]=100.;
	f[0]=3.0; f[1]=8.0; f[2]=15.0; f[3]=24.0; f[4]=29.0;f[5]=50.0;

tri_matrix(n,a,b,c,f);
for (int i=0; i<n; i++)cout<<f[i]<<endl;

}

int tri_matrix(int n, double *a, double *b, double *c, double *f)
{
	int kk;
	double w;
	f[0]=f[0]/b[0];
	w=b[0];
	for (kk=1; kk<=n-1;kk++)
	{
		b[kk-1]=c[kk-1]/w;
		w=b[kk]-a[kk-1]*b[kk-1];
		f[kk]=(f[kk]-a[kk-1]*f[kk-1])/w;
	}
	for(kk=n-1; kk>=1; kk--) f[kk-1]=f[kk-1]-b[kk-1]*f[kk];
	return(1);
}