add numerical recipes library

lib/nr/ansi/examples/xvander.c

@@ -0,0 +1,43 @@
+
+/* Driver for routine vander */
+
+#include <stdio.h>
+#define NRANSI
+#include "nr.h"
+#include "nrutil.h"
+
+#define N 5
+
+int main(void)
+{
+	int i,j;
+	double sum=0.0,*w,*term;
+	static double x[]={0.0,1.0,1.5,2.0,2.5,3.0};
+	static double q[]={0.0,1.0,1.5,2.0,2.5,3.0};
+
+	w=dvector(1,N);
+	term=dvector(1,N);
+	vander(x,w,q,N);
+	printf("\nSolution vector:\n");
+	for (i=1;i<=N;i++)
+		printf("%7s%1d%2s %12f \n","w[",i,"]=",w[i]);
+	printf("\nTest of solution vector:\n");
+	printf("%14s %11s\n","mtrx*sol'n","original");
+	for (i=1;i<=N;i++) {
+		term[i]=w[i];
+		sum += w[i];
+	}
+	printf("%12.4f %12.4f\n",sum,q[1]);
+	for (i=2;i<=N;i++) {
+		sum=0.0;
+		for (j=1;j<=N;j++) {
+			term[j] *= x[j];
+			sum += term[j];
+		}
+		printf("%12.4f %12.4f\n",sum,q[i]);
+	}
+	free_dvector(term,1,N);
+	free_dvector(w,1,N);
+	return 0;
+}
+#undef NRANSI