simp2.c

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#define EPS 1.0e-6

void simp2(float **a, int n, int l2[], int nl2, int *ip, int kp, float *q1)
{
	int k,ii,i;
	float qp,q0,q;

	*ip=0;
	for (i=1;i<=nl2;i++)
		if (a[l2[i]+1][kp+1] < -EPS) break;
	if (i>nl2) return;
	*q1 = -a[l2[i]+1][1]/a[l2[i]+1][kp+1];
	*ip=l2[i];
	for (i=i+1;i<=nl2;i++) {
		ii=l2[i];
		if (a[ii+1][kp+1] < -EPS) {
			q = -a[ii+1][1]/a[ii+1][kp+1];
			if (q < *q1) {
				*ip=ii;
				*q1=q;
			} else if (q == *q1) {
				for (k=1;k<=n;k++) {
					qp = -a[*ip+1][k+1]/a[*ip+1][kp+1];
					q0 = -a[ii+1][k+1]/a[ii+1][kp+1];
					if (q0 != qp) break;
				}
				if (q0 < qp) *ip=ii;
			}
		}
	}
}
#undef EPS