Seidel迭代法

PS:e为误差值，自己设定

#include
#include
#define N 3
#define col 3//列数
#define row 3//行数
void print(double a[row][col]) {

	for (int i = 0; i < row; i++)//找到最大主元，记录行号和列号
	{
		for (int j = 0; j < col; j++)
		{
			printf("%f  ", a[i][j]);
		}
		printf("\n");
	}
	printf("\n");
}

void printXY(double XY[N]) {

	for (int i = 0; i < N; i++)
	{
		printf("%f  ", XY[i]);
		
	}
	printf("\n\n");
}

void Seidel(double X[N],double b[N], double a[N][N],double e)
{
	double p;
	for (int i = 1; i <=N; i++)
	{
		X[i-1] = 0;
	}
	do 
	{
		p = 0;
		for (int i = 1; i <= N; i++)
		{
			double t = X[i-1];
			double sum = 0;
			for (int j = 1; j <= N; j++)
			{
				if (j == i)
					continue;
				sum += a[i-1][j-1] * X[j-1];
			}
			X[i - 1] = (b[i - 1] - sum) / a[i - 1][i - 1];
			if (fabs(X[i - 1] - t) > p)
				p = fabs(X[i-1] - p);
		}
	} 
	while (p>e);
}

int main()
{
	double a[N][N] = {	{ 4,3,0},
						{ 3,4,-1 },
						{ 0,-1,4 },
						}, 
		b[N] = {24,30,-24}, X[N] = { 0 },e=0;
	Seidel(X,b,a,e);
	printXY(X);
	getchar();
}