#include <math.h>void sprsin(float **a, int n, float thresh, unsigned long nmax, float sa[],	unsigned long ija[]){	void nrerror(char error_text[]);	int i,j;	unsigned long k;	for (j=1;j<=n;j++) sa[j]=a[j][j];	ija[1]=n+2;	k=n+1;	for (i=1;i<=n;i++) {		for (j=1;j<=n;j++) {			if (fabs(a[i][j]) >= thresh && i != j) {				if (++k > nmax) nrerror("sprsin: nmax too small");				sa[k]=a[i][j];				ija[k]=j;			}		}		ija[i+1]=k+1;	}}