add numerical recipes library

lib/nr/k_and_r/recipes/qrsolv.c

@@ -0,0 +1,16 @@
+
+void qrsolv(a,n,c,d,b)
+float **a,b[],c[],d[];
+int n;
+{
+	void rsolv();
+	int i,j;
+	float sum,tau;
+
+	for (j=1;j<n;j++) {
+		for (sum=0.0,i=j;i<=n;i++) sum += a[i][j]*b[i];
+		tau=sum/c[j];
+		for (i=j;i<=n;i++) b[i] -= tau*a[i][j];
+	}
+	rsolv(a,n,d,b);
+}