add numerical recipes library

lib/nr/k_and_r/recipes/simp2.c

@@ -0,0 +1,34 @@
+
+#define EPS 1.0e-6
+
+void simp2(a,m,n,ip,kp)
+float **a;
+int *ip,kp,m,n;
+{
+	int k,i;
+	float qp,q0,q,q1;
+
+	*ip=0;
+	for (i=1;i<=m;i++)
+		if (a[i+1][kp+1] < -EPS) break;
+	if (i>m) return;
+	q1 = -a[i+1][1]/a[i+1][kp+1];
+	*ip=i;
+	for (i=*ip+1;i<=m;i++) {
+		if (a[i+1][kp+1] < -EPS) {
+			q = -a[i+1][1]/a[i+1][kp+1];
+			if (q < q1) {
+				*ip=i;
+				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[i+1][k+1]/a[i+1][kp+1];
+					if (q0 != qp) break;
+				}
+				if (q0 < qp) *ip=i;
+			}
+		}
+	}
+}
+#undef EPS